I am soon get a 35 superior. It is a late one with the small plate on front of the head. tag is present along with the crank guard and the factory cast iron side shaft gear guards. it has a bolt on clutch, my question is, how high do the serial numbers go? this one is 20,xxx., any hints on production dates. also, I have the chance to buy a 35 superior with flat mounted main bearing caps, is that an early one? the head plate is large with no markings. thanks.