Ford made the C-6, 4eod, 4sp and a five sp for the 9th generation f series pic up truck.
Each transmission was made to fit a total of eight different engines from the years 1987 thru 1991.
There are only four transmission made to work. They all fit the engines ford made for that truck, they all will work.
As I said earlier if you know prove it. If you don't know say I don't know.