are the mcculloch inner shrouds the same for a 49 and a 91 series?
Yes, a kart and a saw inner are different in that the saw does not have the notches to get at the head bolts. The mc5 inner is also different being the plug enters from the exhaust side. Otherwise as far as I know all the standard series shrouds are the same for the inners.
Steve you just take a chain saw file and make the notches for the head bolts. If you need covers E mail me. there are a lot of them close to you.