do what i did and go find a old trailer hitch reciever under a truck in a junk yard and cut a chunk out of the side of the frame of it and then bring it back and take ur tip off ur muffler and draw a circle and cut that more with a cutting torch, then grind the outside so that it will fit in the end of ur muffler then drill ur holes, MAKE SURE YOU DRILL YOUR HOLES FIRST, I FORGOT TO DO THAT SO MY HOLES WERE ALL OFF CEPT THE TOP...then bring to a welder and he does his stuff then u smooth it all out and stick it on
i found that with a 2in pipe on the end of an HMF utility exhaust it gets very quiet but when u get on the gas it sounds like i cant even describe what it sounds like