Audio Systems: 1999 Silverado sound system install, inline fuse, minor glitches

Question
I'm installing a sound system in my friend's 1999 extended cab with some difficulty.  I've installed systems before with only minor glitches, but i can't figure this one out.  I'm using his factory head unit (he likes the cd player and his Sirius is hooked up to it), a custom MTX box w/ 2 10" subs and two kenwood amps (kac 8402 and 7252) for the subs and other 4 speakers.  all was smooth until i got in the dash and found that the wire colors didnt match the schematic i had.  i'm reasonably certain that there's no remote turn on from the head unit so i tried splicing the remote turn-on into the 12V ignition wire and did a test.  the amp worked for awhile but would flicker on and off.  i figured i had a bad amp power connection but adjusting them didnt fix the problem, and then the amp wouldnt turn on at all.  next i tried splicing the turn on to the heater's turn on with no luck and tried the turn-on to the battery terminal with similar results.  now the hu wont come on when the key is on, but it DOES come one when the key is turned back to ACC.  i checked the fuses and i think i replaced all that were bad.  i'm pretty stumped on this one especially since the amp wont turn on even when directly connected to the battery; i don't want to continue wiring without knowing i'll be powering the amps.  could it be the battery?  i have an inline fuse in the amp power line and am using good connections.  i'm not sure if i'm chassis grounded, but i'm at an impass; any help you could give would be greatly appreciated.  

Answer
Hi Adam!
First of all you have to be sure that you are feeding the amps with a good current source, to do so you'll need to do a simple test, get a 12v lamp (55w or even 75w) put some wires on it and connect it to the wires that suppose to feed the amp, (carefull with your fingers and with the upholstery!!)live it on for some minutes and check if the ground point(where the ground wire meets the chassis)is hot then you need to make a better ground (scratcing the paint or putting several screws togheter, after that check that the remote is appropiate (with a v meter is enough if you have over 10v if your radio has no remote out use ignition or acc, it should be for sure on the radio)after you got correct powering start checking the signal, remember to try the setup with the engine running to get better voltage and to check for possible noises.
Good luck!!