Tom M.- #49 snowthrowers SN 5,834 & lower did not have the shearbolt style of rotor (unless it has been changed). This change was made in 1970 or 1971, I'd have to dig up the service bulletin to give you an exact date. #37A snowthrowers SN 115,001 and lower, as well as all #37 snowthrowers also do not have the shearbolt rotor and were changed at the same time.
Brian M.- Unless you already have the 317 hitch and want to fabricate, then no. With the prices that both styles of these hitches bring, if you still have to purchase it, you are better off to find the correct one (316 Onan, 318, 322, 330, 332, 420 & 430 tractors use one style while the earlier tractors such as the 140, 300, 314, 316 Kohler & 317 use another, although an original 140 hitch won't fit the 300 series unless modified, but the 300 series will fit a 140).