While you're at it I would shy away from the 61 tranny too. The 2 - 3 slide hub has a habit of letting the brass synchro bushings slip out of the hub if you try to shift it very hard. If you want to stay with a 3 speed then get one from a 65 or later Chevy car, 1/2 ton pick up, or van. They are somewhat stronger and all have a fully synchro first gear. Depending on the year and assembly point of the donor vehicle those 3 speeds are either Muncies or Saginaws and are internally the same as the 4 speeds except for the added gear of course.
