So far I don't have to do any cutting on the cowel. Now this is with a bennett smoke muffler. This is why I need to know about the **** on the side of the US41. Now I will have to either bend the pipes or cut them off and add a couple of 45 degree elbows to get the pipes out side the cowel. I'm still useing the stock ignitions system and the spring starter. Thats about it for now I don't have a scanner other wise I would post some pictures for you guys.