I bought the wrong transmission for my 66.

I bought the car with the 833od conversion, done in 2003. Everything looks factory, so whoever did it done it good. Downside is they installed a truck 833, essentially a B/E unit. My bell is aluminum, but don't know if it came from a truck. It should be 5.125 bearing retainer. My 833 has the slip yoke output shaft. I just aquired a 833 A body, but it won't work without doing modifications, buying A body shift linkage, buying a 307 bearing retainer to fit the bellhousing, and would have to buy another driveshaft. At least you are at a stage where you can get it right the first time. It sounds like you will need a car bell housing for the Z bar, unless you go hydraulic, then you don't need the Z bar.