Transmission interchangeability

[Auto5guy]

I have a 73 250 black engine and a lower end from a 74 jackpiner.  How interchangeable are the transmissions in these two engines?  The manual shows them having the same gear ratios.  Can the entire countershaft and mainshaft clusters be swapped out or just certain gears or none at all?

Also the 73 engine has a large kickstart shaft.  Larry Perkins told me that he had personally never seen a 73 250 come factory with a large shaft and it was most likely converted later to fix a broken small shaft.  He did say that it was possible that some of the later 73 250 models came with a large shafts and he may not have seen them.  So has anyone ever seen a factory large kickshaft on a black engine 250?

Thanks

Matthew

[Rocket]

Matthew
I think you can use all of the transmission parts from the Jackpiner.  The kickstarter shaft and the clutch basket are  different.  I believe everything else, transmission related, are the same.
Rocket

[Auto5guy]

Thanks for the info Rocket.

Matthew