I've owned a Roper 18T for years, the 18hp Onan used one muffler that was over $300.00 in the early 90's now NLA. I cut the ends off and welded male nipples to fit the large round repl. mufflers. The belt cover on the deck is a good idea in theory, but is almost impossible to clean under and it needs cleaned often or will rot the deck. This requires deck and pulley removal to do right. My Roper is used hard and often, so this was removed. xangussupplyx e-bay has the 5/8x103 6941R belt for $29.99 free ship. Do not get the one that says fits 6941R & 6943R. The 1/2x92 in. 6943R is $25.99 free ship again do not get the one that says fits both. The 6943R is for the 48inch Mower. These belts are both kevlar wrapped, my experience is that non wrapped belts last about one season where the wrapped ones last several. mowerparts4less e-bay has the 6943R for $20.10 free ship. I've used both companies and very pleased, very fast shipping.