I have tried to figure out a way to do this with a transmission on a workbench and it simply will not work. To have a correct shift pattern the levers on the transmission need to point up and the 2 bosses for the pivot bracket are in the way. 63 and 64 truck 3 speeds will bolt up (may need to shorten driveshaft) and can be converted to floor shift. I am looking into making a bracket for the clutch. Search on Ebay for F100 top shift transmission. This is one that I converted to top shift and am looking for a 53-56 side cover to try and make a pattern for the bracket.
Mike.