A few pertinent points: Use, Money, Thoroughness come to mind. Used trans are cheap and a BIG crap shoot. If they are off, they probably have problems. I was 3 for 3. Finally gor a new low speed drum and went through it. GET THE BOOK.
Looks dry for 30 years, so dont be surprised if something else breaks coming apart. In that condition I would scrutinize every single piece that came off. You can buy rebuilt gears from the vendors but they charge for the non usable core parts. You will learn much grasshopper!
It would be prudent to go through the entire flywheel and MAG coil and crankshaft stuff while in there besides braring, rings and valves. Personally, Id consider a decent running take out (several on edog right now) or put 2K+ into this one. Honestly, it looks pretty tired. Get another and part this one out. It may have even bent the crank end and then... ws
