Adding Muffler Pipe to Craftsman Riding Tractor?

we built a pulling lawnmower tractor once and we used a motorcycle muffler for a stack pipe. if you go to a lawnmower repair shop and tell them what engine you have they can show you the different types of mufflers you can get. you need one that starts from the motor as a pipe and cut it off and weld the other pipe to that. if you want it to look like a semi truck you,ll have to cut the top off flat and check at a truck stop or tractor supply shop for the right size flapper.