When I was restoring my 61,I was bound and determined to keep the old girl as original as possible. 235 with a three on the tree as well as drum brakes all around. Now that it's been done a few years, I kind of wish I did some upgrades. The main thing I would like to do is add disk brakes up front. The old style manual just is not up to par with today traffic for my liking.
Keeping the three speed is a must, but my top speed is about 50-55 mph. So I'm thinking a three speed with overdrive.