I have the heavy duty, granny low, 4spd in my 61 and I am wondering if there are any other manual transmissions that would fit this thing. Particularly I am looking for somewthing with an overdrive, maybe even a 5spd? I am thinking of replacin the 4spd, and regearing the rearend altogether. I really want to be able to drive my truck on the highway at 65-70 and not feel like I am going to make it blow up, thoughts and ideas appreciated
