Installing 1970 Mustang Gauges in my bump

[68muscletruck]

I recently picked up an entirely functional gauge cluster from a 1970 Mustang, I hope to install them in my 68 F100 as none of my original cluster works save the speedometer/odometer. I would love if the original gauges worked but I have no clue what may need to be done to make that possible, so being a hot rodder I began looking for other options and of course, a bigger set of numbers on my speedometer. I have the entire wiring harness from the same car I pulled the gauge cluster from and noticed that the Stang's setup includes the film on the back of the housing that the wiring goes through for the lights and gauges with one large plug that goes in the back to connect the gauges to the car's electrical system as opposed to the setup in my truck where each gauge has a set of 2 wires that goes to it with no backlighting for the cluster. As I wandered through the junkyard the other day looking through a few bumpsides I looked at a few closer in age to the Mustang Cluster I found. I noticed in several 70-72 pickups they have a similar wiring configuration for the instrument cluster, the film on the back of the housing that the wiring goes through including the twist in and lock spots for the backlights, and again one large plug for the entire cluster instead of individual wires to each gauge. Has anyone done this before or know if the plug would match up from the truck and the mustang so I could just get a new 70-72 wiring harness and install it in my 68 and plug in the new cluster or will I need to do some further research and find another way to wire it in possibly using the mustang's harness?

[FORDification]

There are way too many variables here, like whether or not the truck and Mustang have idiot lights or full gauges, not to mention the all the mods that would be necessary to fit that panel into a truck. I'm not necessarily trying to talk you out of it, but it seems to me that it would involve a LOT less work to just get your original gauges working...they're actually very simple, and we could walk you through that. Either that, or go with an F600 gauge panel, which will bolt right up and look a lot more trick.

[68muscletruck]

they both have full gauges, as for inserting the cluster in the dash, I don't plan to use the original mustang bezel, just the gauges in the white housing, my father works at a local sign fabricating company where i can cut and fit clear coverings for the gauges as well as a panel to mount over them that would bolt right onto the original truck 'bezel' with the center cut out entirely so it would mount just hte same in my dash, however I would like to know what I could do to get the originals working before I begin something that could take weeks or months to make correct even though the fabricating to mount it would only take an hour or so, and also where could I find such a dash from an F600?

[FORDification]

...however I would like to know what I could do to get the originals working before I begin something that could take weeks or months to make correct even though the fabricating to mount it would only take an hour or so...

More than likely, the plastic sheet on the back of the instrument panel has been damaged or corroded, so a visual inspection of that is the first step. If that appears in good shape and is clean, then you can troubleshoot the individual gauges. The fuel and water temp gauges can be tested by simply removing the wire to the sending units and grounding them and then watching the gauge. If they're functional, the needles should swing over to the maximum reading.

...and also where could I find such a dash from an F600?

E-bay, the Parts Wanted classifieds here on the site, or just keep an eye out in the junkyards for a late-'60s/early-70's F500-800.

[68muscletruck]

Thank you for the response, however, the Mustang cluster and the 70-72's I saw at the junkyard were the ones that had the plastic film on the back, my truck doesn't have that, all is in order on hte Mustang cluster its in great shape, no corrosion or anything, we tested the gauges at the shop i work at... as for MY truck, each gauge has simply two wires connected to the back, no plastic film of any sort, so how do I test those?

[FORDification]

Whoops....my fault, I misread. The fact that you have hard wiring going to the gauges only makes it that much easier to troubleshoot.

Testing them is the same...just ground the wires to the sending unit, and watch the gauges. Report back what you find out.

[68muscletruck]

alright, will do, it may be a day or two as i've been reworking some stuff under the hood to convert to electronic ignition etc and that project is priority for the time being... I'm 18 and working at a local mechanic shop as a 'mechanic in training' or whatever you want to call it, (i began building the truck when i was 15 so I've learned a lot to this point) but my knowledge still has gaps here and there so you'll have to explain 'sending unit' for me... There's a Fuel, ALT, Oil and Temp gauge, where would I ground each of those?

PS, the fuel gauge works intermittently and I believe off by about 1/4 tank... possibly a bad ground to the tank sending unit, I'll investigate and report back

[FORDification]

You can't have a bad ground going to the sending unit....the sending unit IS the ground. That's what a sending unit is....a variable-resistance ground. By altering the amount of resistance, the gauge reading can be affected.

Let's start with the fuel gauge. Read the following tutorial, just to educate yourself in how it works:

http://www.fordification.com/tech/fuel- ... -units.htm

The fuel tank is behind the seat. Right on top of the tank, you'll see a wire connected to the sending unit. With the ignition key in the ACC or ON position, pull that wire off and ground it to a good clean ground, which should make the needle go to the FULL position. When you disconnect that wire, the gauge should ready EMPTY.

[68muscletruck]

Hey thanks for steering me in this direction, I have not had time to test my gauges yet, i plan to do that tomorrow afternoon before our family festivities begin for the holiday but i've decided to track down a gauge cluster from an older f500-800 like you showed me and i'm going to put the mustang gauges on the local ad listings for sale as i really like the style of that more. I will let you know how the testing goes tomorrow.

[FORDification]

There's one on E-bay right now that someone painted flat black...but you can't beat the price. (As of this posting, it's $12.95...but will surely go higher.)

http://cgi.ebay.com/ebaymotors/ws/eBayI ... K:MEWAX:IT

[68muscletruck]

I still may look into getting one of those later down the road, after installing my 'electronic ignition' distributor, all of my original dash gauges started working, go figure, so now that thats all functional I start moving on to some other interior ideas i have, namely paint and sound system, thank you for all of your help!

[red403]

what years f600 are the gauges out of?

[68muscletruck]

Turns out the wires for my oil and temp gauge were just snipped at the edge of the manifold and the sending units for them were removed for the add on cluster (oil, temp, alt) gauges in teh middle of my dash from the previous owner, no suprise none of those work, but the originals have been tested and after getting the sending units for each they will work again. I have another question however, 2 years ago shortly after buying hte truck I bought a new fuel tank sending unit from LMC TRUCK for like 65 bucks or something ridiculous like that and it stopped working properly about 6 months ago but once in awhile the gauges goes past empty, can i do something to fix/recondition that unit so I don't have to buy another one?

[rjewkes]

might be the IPVR it's supposed to control the voltage to and from the guages if it goes out of wack your guages will all be off also i beleive the guages also have a fuse that if blown will cuase the readings to be wrong or irradick.

[68muscletruck]

I'm going to a local 'BIG TRUCK' junkyard tomorrow that I was told has a bunch of those F500-800 gauge clusters etc and before I go I was wondering, do the wires on back that just slip onto the back of the gauges like the original rectangular F100-250 gauges? I got all new sending units for the oil and water temp and just want to know if they connect the same before i go?