The only transmission I ever overhauled without assistance was the 3-speed from a 1942 Harley-Davidson WLC war bike. I did it on my shop bench with the service manual in close attendance. But I know your 3-speed to be a simple, durable unit and there are still millions of them out there in wreckingt yards and old gearbox overhaul shops. When I was 14 I worked in a shop doing nothing but stripping those 3-speeds and washing the parts.
