i suggest replacing the deck also so you have the RCA outputs for the amp
you need a wiering kit, and make sure you securly mount the amp! you dont want that thing flying round!
as for the power connections, run the red mai power to the Battery and attach it to the positive (+) terminal, then mount the dround to the chassis. i suggest findong a hole, sand the paint and ground it there!
the remote wire only needs like .5 amps to run, thats it, it should be on the new decks wiering harness, or if you decide to keep your stock one, then like what was said before, attach it to the 12V igniton, i suggest finding it on the radio circut, makes things easier just in case you blow the circut, it wont confllict with anything really important like the PCM.
oh and another thing, STAY AWAY FROM THE SRS SYSTEM, you dont wanna be fucking with that!!!!!!!!!!
BTW, what kind of amp is it and what are you going to be pushing with them?~