I found out a while back ago that rigid frames are more destructive to the motor mount boss than a swing-arm frame. The flexing and pulling of the frame loosens the bolts and starts twisting and breaking the bosses. 1958 and up cases are usually in better condition due to this. The cam bushing cracks are very common. Some look like spider webs they are so bad . . . I will grind out the cracks a bit, clean it fully (propane torch and brake-clean spray), get all the oil out so it's not poppin' at him . . . and take it to a new welding guy I found - see if he can repair this case ?