What year is it? Does it have AIR? If so, you're in for some fun. The pulley for the AIR pump is on a sort of a tripod affair that straddles the blower. It has to come off first. Looks easy- 3 M6 bolts- but once they're off, the thing is aligned with roll pins. Probably frozen fast! Oh yeah, and you can't even see the other pulley, the three bolts, muchless the rollpins.
Hopefully, he doesn't have a '75 or '76 so he won't have to deal with it...
Good luck!
Jim
PS- found this picture of a 912E. You can see the extra pulley and the three M6 bolts I was talking about..... Again, I hope you don't have to deal with this...
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