Hey all. I have a B6 A4 and just recently the drivers side speakers died on me. I know this is caused by the wire harness in the door jam breaking. I can wiggle it and it will turn back on. Problem is that when I close the door again they turn off.

I have an aftermarket head unit also; I believe it's installed correctly, but the rear speakers are lacking.

So here are my questions -

I have two aftermarket amps
Kenwood KAC-X621 179Wx2
Kenwood KAC-X541 88Wx4

I also have two 12" subs and an infinity 10" sub.

My question is this - can I easily replace the stock amp that powers the rear speakers with one of these and install maybe the infinity 10" sub? How would I go about doing this? I figure I might as well use these since I have them (even though they're old) while I rewire the front speakers. I'm just not sure about the wattage ratings and amperage ratings. Thanks