The wiring harness in my '88GT looks much better (ie, almost new) at 15 years old than the one in my '95 Contour did at 7 years old (cracking and breaking, bare wires, etc).
I've had no electrical problems with the '88GT, and the wiring is in fine shape.
There was a problem with some (maybe all) '89 models where the wires to the connectors that connect the engine harness to the fuel injection harness are supposedly too short, this was addressed with a recall which consists of a couple of extensions which are added. Supposedly this can cause a check engine light and fluctuating idle problems.
I put them on my '88GT (the parts are most likely discontinued from Ford by now..I was only able to get one from Bill Jenkins, the other I had to get from Green Sales Co.) to try to fix a problem which caused an "EGR position sensor voltage low" code, but that turned out to be a bad vacuum line (the one I cracked..maybe it was already cracked and I made it crack all the way through?)
