The problem with these restos, is that you never really finish them! as you can see, I recently acquired a NOS case saver and sprocket guard for my PE250. I fitted them yesterday.
The crank case has 4 mounting points
Mount 1 and 3 carry both the case saver and guard, while mount 2 only holds the guard and mount 4 only holds the case saver. Mount 1 and 2 are complete and serviceable Mount 4 had half the perch snapped off and mount 3 was virtually non existent. Mount 4 had plenty of meat left at the base of it, so I drilled it a bit deeper and installed a helicoil, then bogged the missing half with some liquid steel. It seemed to go quite hard, so I ground it back and fashioned an acceptable perch.
Mount 3 was lucky if it had half a thread, so I drilled it a little bit deeper (not as much room to play with here) and tapped a helicoil in here also. Now all I need to do is fashion a long spacer to support the guard and saver and the jobs done!
Quite happy with the end result.