Windshield wipers won't stop.

it's possible your wiper interval govenor is going bad or your motor is going south.either are common problems for the ford fox body.

wiper switch possibly?

The wiper park feature has probably gone bad. The wipers motor has a switch inside that continues
to provide power to the motor when you turn the switch off. This switch provides power until the
wiper blades reach the park position. Once the wiper blades are in the park area, the switch cuts off.

If you remove the wiper motor and then carefully remove the cover that has all the wiring
connections, you will find the park switch mechanism. There are two copper circles and two brass
strips that act as contacts mounted on the fiber gear that moves the wiper arm shaft. Sometimes
the copper circles come unglued from the gear and then the park feature doesn’t work. I epoxied
mine back in place with some JB weld and it has worked good for several years now.

The following diagram is for a 92 Mustang: some of the wire colors and connection points may be
different from an 88, but it helps give you an idea of how it is wired.

To remove the wipers pull up on the arm a bit and pull out the little tab (at the hinge) with a flathead screwdriver and then set the arm back down and theyll come right off.

Bumping an old post, so i got all the way to getting the cover off, and getting the one bolt that connect the arm under the cover to the motor. it is still sticking to the motor though i tried gently prying with a flat head, am i missing another screw or something towards the driver side of the car. i was looking but i didnt see any visable bolts or screws.