Hey guys, my H&S XRT Pro just arrived. I would like to install it, but i want to finish parting together my exhaust setup. Im a bargain hunter, and i sourced a brand new 4" 2 piece flo pro downpipe for 65 bucks. Now i want to complete my setup with a 5" down pipe back setup. Im having trouble getting information. At what point would it step up from 4" to 5"? Im also having trouble finding a coupler of some kind to step up to 5". I know i could have bought a complete kit, but like i said i look for deals. I have less than 500 invested in the XRT tuner and downpipe combined. If anyone has some info, i would greatly appreciate it!