Dellman, I'm not familiar with your year of truck, but most GM vehicles had a transmission crossmember that bolted to the frame.
There was no cross member for 1960-66 Chevys with 3 speed short tail-shaft transmissions that I know of. I have another 66' 3 speed truck and have seen many other trucks of my year with 3 speeds and none of them have cross members. Curiously there are two bolt holes of the tail-shaft where is appears a cross member could be mounted but I believe that virtually the same transmissions were used on other models as well.
