I knew nothing about these units before I rebuilt mine. Someone described them as 'bone simple,' which they are...but brilliant in how they were engineered to work and interface with the driver.

I did up a thread on my rebuild process that you may have already seen. Got help from cletis and Fred and many others on the way who understand these things very well.

My trans was an SM319 and I rebuilt both the trans and the OD, but had no prior experience. You can do this.

If you can find someone (like cletis did) who will rebuild it for less than $300, jump on it. I spent much more than that in finding good useable old parts. These things also have dedicated electrical components that need to be either refurbished or replaced, and there are a variety of opinions here on how to rig up the electricals so as to operate the OD to suit the driver. I put mine back to stock and have been very happy with that decision.

Let me know if you need pictures of anything. I took several so that I did not forget how it all went back together.

Best,

Jim

1957 Chevrolet 3100 Stepside
235, 3-speed w/OD
In the Stovebolt Gallery