So I noticed that I start overheating at idle, but at highway speeds it runs almost normal. So when it was sitting in the driveway, after idling for awhile, trying to figure it out, I shut it down, and saw that my fan was freewheeling, which means bad fan clucth. So my question is, what would I have to look out for if I were to convert it to an electrical fan system instead of a mechanical fan? Advice here would help a bunch.

1985 Supra 5MGE (Stock)

it free wheels a lttle when engine is shut off, probably need a new radiator. I had the same problem, I got it flush by radiator shop and was ok for awhile then started again (too much corrosion blocking the passage ways). Replace with a new one. Are you using the fan shroud? especially with the a/c on at idle, the fan shroud is a must.

not running a/c at all. infact have the fuse pulled for the compressor, and have the belt off. It was the fan clutch though. There isnt supposed to be any freewheel at all in the clutch, even at cold temperatures. and the seal went out it and leaked the oil all over the fan. So I just replaced the clutch and now it works fine.

1985 Supra 5MGE (Stock)