To add to the above I have never done the twin trans conversions for power or OD but this is the way dad and Grandad did it. You seen more of this in states where guys raced top end. I knew a fellow from Ill. that had a flathad merc with OD and a 2 speed rear end that was able to lay modern cars to rest in the 60s if they wanted to race top end. If you want to think of a scary thought , think of the tires we were running back then. Then think about the 20s & 30s cars with mechanical brakes. Its a wonder anyone is still alive.