I can't figure out what you could have wired into to get power from the parking lights. I just put a new Alpine into my 85 and I found the schematics in the back of the haynes manual to be very helpful. I cut the connectors off of the old stereo and amp and used them to make a wiring harness with the Alpine cable which comes with the stereo. I am assuming you pulled out the amp which is under the headlight switch like I did. The new Alpine I bought has more power in the main unit than the old Volvo amp so there was no need to keep it. I just ripped it out and used the speaker connector to make another harness to for the rear two speakers. Hopefully you did not tap into the lighting power. I highly recommend making a soldered harness using heat shrink to cover all the soldered connections. It took me about an hour to make it but worked perfectly and heat shrink protected connections last longer. It also makes for a very clean installation which is easy to remove. If you look at the schematics, the colors are pretty easy to figure out except that black is SB. I am not sure what the S means unless it's "solid" black.