[rsavage]

Several years ago I replaced the non synchro first 3 speed in my 66 with an M20 which was a 10/27 spline. I think it was a 69 transmission. I bought a Hurst competition Plus shifter that was supposed to work for trucks, but the handle had to be cut and rewelded at the base to clear the bench. Even now it is up against the bottom of the seat in 2nd and 4th. Obviously the 3 speed floor shifter hole in the floor isn't going to line up with the 4 speed as the shifter is on the rear of the tranny. If I recall correctly, driveshaft was real close. See if you can get a 27 spline yoke that is about the same length as your 3 speed yoke.