MSD ignition installed, now I'm thinking transmission time?

I installed the HEI module with a 12v epoxy coil and had roughly the same results, nice smooth idle, improved acceleration, easier starts hot and cold. (now if i could just get the choke working )
The a833-OD is probably the easiest for a straight swap, I did mine in a weekend. I had it all laid out on the garage floor prior to the install and swapped in the pedal assembly a couple of weeks before actually pulling the 904.
With the OD 4-speed it runs about 2250RPM at 70MPH and gets about 24mpg last time I checked.
Another thing that helped the ol' slant was to get rid of the stock solid fan setup and switch to an electric fan. The solid setup just put too much drag on the engine, and without the fan running during warm up, it gets up to temp within a mile of driving