A constant hotwire is nowhere to be found, so in the mean time I decided to hook the constant and accessory wires to the 12v battery wire so I could hookup the speakers and worry about the constant later.
Now when I go to hook up the speakers, the sound comes and goes.
I could hook up 3 speakers and all of them work fine, but when I get to the last one, I connect the wires and all of the speakers stop working.
Could this have anything to do with the fact that I'm running the accessory line to the battery?
you should get an adapter for your stereo that plugs into the factory harness connector and into your new stereo connector.
that being said, white/yellow wire should be battery+ don't mix this with yellow/white wire for pwr antenna.
red/black is for then light circuit. don't use this for ground! it will appear to be a groung because the lights are not on and it grounds through the light bulbs. but if you use it for a ground and then turn on your lights you will have a huge mess to repair.
are you sure you are pairing up the right wires for the speakers? do you have a wiring diagram to go by? A wire harness adapter will save you a lot of work and time (and money if you make a mistake).