Hi Andy, I believe that the SB Model 33 (first introduced 1953) had metal clutch housings...I am not sure about the first model Scotty 45's....I am lead to believe that they were alloy....
BTW. There has been discussion of late where the clutch assembly has been thought of as a flywheel....this is, of course, incorrect....the flywheel is on the other end of the engine (also supplying the electrics)
