CRF 250R Pipe Question

A rivet has come loose at the end of my pipe and after one more day of riding they became ALL loose. Some holes that hold the rivets have stretched to the point that a fissure was created. I am going to repack the silencer and change the rivets, but i am wondering if those will hold since some holes are not "holes" anymore (I hope this isn't too confusing because I really can't explain it better without a picture). Should I cut the pipe and the "carrot" by 1/2 an inch and make new holes? Will this have any effect on performance?

Ok I realize how much this is unclear. Lets put it this way: Will cutting the silencer by 1/2 an inch have any effect on performance?