Try contacting the people at MEACO Motorsports. Somewhere I saw a picture 427" sidepipes with a SUPERTRAPP adjustable muffler inserted into the tip.
The "SUPERTRAPP" is held in place with springs...tabs are welded to the exhaust end.
http://www.maecomotorsport.com/Index...e6TheCars.html
SuperTrapp: Performance Exhaust
Wish I could fine the pictures. At one time I thought there were at the MEACO website but I don't see them this evening.
Pete