You need a 92 - 96 F-150 manual trans. 5.0L starter, it is a specific unit. The positioning of the ring gear on the flywheel (depth-wise) is different between the truck and the SC flywheel. The original SC starter (which is the same as a passenger car 5.0L unit) will grind if used with the truck flywheel.
I ran into this when swapping in a McLeod flywheel in my SC. It was an early version that had the ring gear in the "truck" position for whatever reason. Dave helped me out of that situation!!