me and my friend just put a set of these https://www.ebay.com/itm/STAINLESS-...863529?hash=item2a13cd8929:g:NXYAAOSwbL1dUbno on a 5.7 vortec. the yipe dose not seam to want to fit. the truck originally had a 305 vortec. I know you can put tbi headers on a vortec and I also know that the 305 and the 350 y pipes are not the same. should me and my friend look for a 350 tbi y pipe or a 350 vortec y pipe?