So my 92 loyale has a digital AM/FM radio with the tape deck. The tape deck is hooked to the head unit via 8 pin DIN. I read a few topics on how to make a cable, but none on how to mod the tape take and keep it.

 

So inside the tape deck there is a pin header that is soldered on the board at the end of the 8 pin cable. This is the pin out:

 

• Blue = Left +
• Red = Right +
• Yellow = Audio -
• Black = Power -
• Brown = Power +12v
• Green = Tape in deck. Turns head unit on, but disables radio.

So you can solder an aux cable to red blue and yellow. It seems the head unit automatically mutes the radio signal when my phone is connected, didn't need to wire a switch to the tape in deck signal

My '86 is so loud and rattle-y that trying to listen to music in it is an exercise in futility. I wish I had the money to soundproof the floorboards and doors. Not that they would be totally soundproof but that would cut down a substantial amount of noise.