My 30 Coupe was damaged in a fire,and a few months ago I stripped the ruined body off it.It has a super clean frame,with a very thin coating of paint on it.Reading here I got to thinking,and went out to check the frame number.It has none.No sign of ever having had one,and no sign of one being ground off.Frame is too clean,smooth,and straight to have had a spot ground down.This is not the first frame I have had or seen with no numbers.A poultry farmer in town brought his and his families collection of A iron down here from Canada over a 30 year period,I got a half dozen frames from him with no numbers.