There seems to be two main trouble areas:
1. The Gear Box Case on the final drive sprocket side, damaged by chan wear.
Need welding and machining.
2. Broken Gear Box Cover where the clutch cable adjuster is mounted.
Can be fixed at home without any special tools.
The gear box cover can be repaired by making a mold from stainless metal sheet and soldering / casting with shavings from an zinc sacrificial anode.
First make a mold. Cut some zinc shavings an make a scraper from stainless welding wire.
Solder with a propane gas torch and zinc.
Break the oxide layer on the gearbox cover with the scraper.
File to desired form.
Drill and thread for Clutch Cable Adjuster.
As good as new and probably stronger.
