YS 140 Muffler question
 

I have a YS 140 I am flying in a sport plane and am trying to get some good flights on it prior to putting it in my CA Models Fantasy. I am having problems with the stock muffler. I have a pipe for it but don't have any place to run it on this model. The problem is the screws keep backing out of the muffler cone. I've glued/loctite ect the screws but they keep backing out. I'm lucky I haven't lost the cone yet (like many others). Anyway, I am going to try one more fix. I drilled the socket head screws and put safety wire on the screws. What are the down sides????????? Also, what type of extension can I put on it without it getting burned off?

v/r
Jerry L.