Anything special I need to know about the Mk 3 wiring
 

At lunch today I figured out how to remove the rubber cover around the head unit and plan to replace the double DIN with a console pocket/single DIN unit this evening. Is there any kind of proprietary wiring connection back there I will need to worry about before I do this? I'd like to finish it in one session if at all possible and would like to have some idea of what I am about to face BEFORE I rip the dash apart.

on my 86.5 mkiii i needed to get the lil wire connector set that converts from the old model cars to the new model stereo units... it was like $5-12 at wal-mart or kragen auto. and none of the colors matched up so make sure you read what each wire is, they are clearly labled. also i would use electrical tape to do the connecting, i went crimps the first time around and didnt have a good connection, good ol black electrical tape substituted in got it done. also the in dash installation kit i purchased from a kragen auto parts store did not fit perfectly, i had to cut some dash rubber/plastic out... but, maybe that was just that one brand i got, i've heard others had no problems. good luck.

I hadn't thought about the adapter kit. The last two times I've done a stereo swap I've replaced a DIN with a DIN. Since the console pocket I bought is DIN sized I just assume the two would just slide in. I have a feeling I am going to be pulling the current head unit out and putting it back in tonight so I can see what I need to get to finish the job.

Okay, I got the radio out last night. The head head unit has two white proprietary connectors on the back and two other wires. One wire is clearly the antenna; the other I'm guessing is the power antenna actuator.

I am guessing I could just pull all the wires out of the plastic modular connected but I don't know which wire is which. I'm also confused about the fact that the Supra has 6 speakers, something I don't believe most head units can drive out of the box.