If im not mistaken,
The 94-96 have an amp in the raido.
In 96 and up I believe there are two seperate amps.
A 10 watt amp for the front speakers and a 15 watt amp for the rears.
The amp for the rears shopld be under the front seat.
Im not sure about the other one.
I think the amp for the front is behind the stock radio like in a fox body and I am pretty sure the rear is under the passenger seat. I am not totally sure how much power they are but I know they are pretty powerful.