There are many ways to solve this problem. I too have a 1950 3100. I went to a 1962 261 engine so I had full pressure and full flow oil filtering, then put a Borg R10 Overdrive transmission behind it. Its a direct bolt up. I then went to a 1955 1st series rear end because that is also a direct bolt up with a 3.90 gear set. I then got new 1954 spec'd leaf springs all the way around and had a 1964 Suburban driveshaft shortened. Since I like the 4 on the floor shifter, I made a shifter that comes up through the floor in the 4 speed location, and that's how I get highway speeds and more reliability out of mine. The entire restoration is documented here:
devestechnet.com
