Hi Ube
Take a look of the pics! Shaft extender and gear are distinct parts.
This is the PAZ1, you can attach extender both in crank and cam, because is the same pattern.
Pay attention to crank, do you see that bolt hangs gear to crank? I think it will be something like that. but blueprints will help... totally.
Cheers
VP
PS: how was bolted shaft extension to crank? with 4 screws?