Don't mess with the electrical system in these cars. They are huge heaps of shit. My uncle bought a new 89 Starion ..it ended up in my hands when i was about 17/18. Biggest piece of shit car ever made. Electricians and some shops refused to work on it. The cylinder heads on them suck. The electrical system is plagued with gremlins (my cars alarm would go off at like 3/4 in the morning all by itself all the time - I just ended up taking the battery out since I nor any one else could find the issue). The power windows would quit rolling/up/down. The A/C would only work when it felt like it. The heat and or AC would turn on, on its own randomly.

As far as modifying them goes... Forget about the stock cylinder head it's trash. The entire fuel injection system would need to be replaced (if not for supporting extra horsepower ... just for some sense of real reliability!)

My suggestion is. Keep the car only if you are going to use it on weekends. Otherwise get rid of it. These cars are huge heaps of shit. The final point of assembly should have had a exit that sent these cars straight into the junkyard if you ask me.