Tom, You will in all likelihood have to pull the engine and remove the pan at the very least to gain access to the governor assl'y for removal and replacement.
The brass bushing has to come out/off first. Best to refer to the FSM.
Of course, if the engine is completely apart, the governor, shaft, bushing and pin are the first parts to go in the block in the re-assl'y process.
I'll be up your way sometime this summer.
If you get the parts and have the engine out, I'd be glad to stick around an hour or 2 on the way to or from Hutchinson help you out
Dave