got an 01 dodge ram reg cab sport.... where is the stock amp located for the infinity system? anyone know?

 

If it's the same as a '97, I'm pretty sure it has Individual amps mounted to the speakers in the doors and cab corners. The backs of the speakers have an odd looking attachment that is proabably a combo amp / crossover for the tweeters. Also, I used a multi-meter on the factory wires and found that it's a straight shot from the stereo to the speaker connectors.

 

Yeah the amp is on each speaker. You can replace the deck without replacing the speakers but not the other way around so do both and your good. 6x9 speakers in the front and 5.25 in the back! don't worry about the tweeter its **** anyway.