Replacing lens curtain crank on Mamiya 7

[Maineiac]

The little crank on the bottom of the M7 that closes the lens curtain split in two (it's pretty flimsy plastic.) For 3 bucks, Mamiya sent me a replacement along with a schematic. It's supposed to be an easy self-repair. I have the requisite tools--jewelers screwdrivers, various tweezers, etc., but it is not self-evident how to get the broken one off. It's just the small part that folds that needs replacing. It's held by a pin similar to that which holds a watchband on a watch, but since the crank is recessed, the pin has no clearance to come out.

Has anyone done this, and if so, can you tell me how?

Thanks.

Larry