Interior electircal problems

[spideys85gt]

ok, i have an 87 gt with an all 90 interior in it. i replaced next to everything. all trim and dash and carpet and seats. the instument cluster in the 87 was only an 85 mph so i took the one out of the 90 cause it was 140 mph. well now my dome light stays on al all times, as does the rear hatch light. they get brighter if i turn the panel light switch up and turn the dome light on that way. both doors are closed. also some of the intrument panels lights arent in sink (like the blinkers and high beam indicatiors.) as of now the computer to the car is not hooked up so i dont know if that has anything to do with whats going on. i'm just wondering if there's some kind of difference between the 87 interior harness and instrument cluster, and the 90 interior harness and cluster.

i also can only get my high beams to turn on when pulling the collum arm back as if to flash the lights

 

[blk92stangg]

Not sure about your other electrical gremlins, but my dome used to stay on too. Come to find out the bumpers on the corners of the hatch were too high, so the light cut off switch wasn't being fully depressed.

 

[89MustangGX]

Unless you changed the wiring harness there, the 90 Cluster is casuing all kinds of problems. Swap the old one back in and look for just the 140 speedo if that's what you want.