Lord help me!

Parts change, doable with out the book. A mechanic would need the book though, and go through the trans and bottom end, for out of spec/normal replacement parts. Or at least I would like to believe. Looking at parts does not always tell the entire story. There are parts in there that if they look shiny and good, they are not, and are worn out. The online parts micro fiches have accurate parts diagrams, no specs though. The 100 dollar question, why did the case break in the first place? Used cases with new bearings and seals? Comparing that old dirt bike engine to your ford is a little off. Pathetically it would be closer to an older F1 race car. And I did not make them like that, but I do hate pushing them back or getting hurt! Vintage Bob

Yes, buy the manual. You'll be glad you did.