So after nearly 20 years driving the '54 with stock 235 and Saginaw 4 speed, I had to do something.
I rejected the small block because it would lead me into an endless upgrade of components and I would result in a streetrod.
So what I finally did was buy a reman 235- but a late 50's model with hydraulic lifters. It bolted right up to my old bell housing and a T5 that came from a late model S10. No blacksmithing required.
It is wonderful - not to have that old Saginaw screaming and the new engine pulls like a 8 cylinder.
And I still have a nearly stock truck. I recommend this solution.