i have a magnaflow 3" single in/out to put on my truck. i just wanted to put it where the stock muffler is, followed by an immediate dump. however, stock piping is 2.75"... all welders around me say the 1/4" is too much and will have a leak, no stores carry a 2.75" to 3" expander and no shops say they are able to do anything for me. I can't even find anything on the internet to buy. Any advice?