what's interchangeable?
 

OK, I'm going to start looking around for some spare parts for the 73. I know most parts are interchangeable, but what about the clutch? I guess that is about the only thing that I don't have a spare of right now. Will the clutch out of any geared NF swap out even? I know the O won't, but otherwise?

Yeah, the narrow frame clutches are all the same, from the 70 all the way to the 126 they'll drop right in.

70,100,71,72 and 73 fenders are the same.

cool, now I just need to start the surplus room :)

clutch plates (both steels, and fiber driving disk ) and all springs are the same through wide frames also. Im not going to say for 82 series. Also, the throwout bearing is the same. The shaft, throwout arm, and an added grease fitting spacer (added on the wideframes) are different.