Radio amp locations?

[Darrman]

Before I get griped out for putting a stereo in, just know that the previous owner had already cut out the radio surround and hacked out holes for 6x9's in the door panels. So instead of trying to repair, I am going to see if the work he did can be salvaged.
Main thing I am wondering, I want to put a small amp, a 4channel in the cab somewhere. No subs, just going to be speakers. What is the risk with the in cab fuel tank? I do pretty decent work installing my systems, but the thought of a vapor leak, combined with a spark somehow, bad thing.
Anyone else have some ideas for locating the amp? Thanks!

[fordman]

under the seat. also there is a bar under the dash that goes from the firewall to the dash that could be a good attachment point and it can be sldie back as far as you want it. towards the firewall.

[lightning_msd]

if its just a little small 4 channel for speakers, then under the seat should be fine