Have 89 fc i just bought,had no tail lights,interior, gauge,blinkers, horn,or running lights,and or tail brake lightsor emergency flashers.what did work; wipers, headlights,pop up headlight switch,hig low beam switch. Removed headlight switch and it had burnt connecters and harness. have 88 parts car with good headlight harness and switch,so i replaced harness and surround with all 88 switch's. now i have turn signals,emergency flashers, interior lights, horn, headlights high low beams,and brake lights. But now i still do not have tail lights or gauge lights,and head light pop up switch does not work now and headlights will not shut off,before popup swich worked and headlights shut off
.also now wipers do not work. so question is can i use 88 switch's or do i need 89-91 harness and switch's? also after key is turned on for30 seconds buzzer comes on and stays on until key is turned off. Thanks for any help

 

If anyone is interested ICEMARK answered my question in lightswitch post on second gen forum today. He said the 86-91 light switch are interchangable but the harness off 86-88 will not work on 89-91......