We were in a bind so we cut the flanges and welded a V band in. It actually helped because we could rotate the exhaust to help with the fitment. I emailed RJC with my concerns and they said they make a transition section to go from the 3” down pipe to the 4” exhaust. But again, I had no idea that was necessary. I just figured everything came with the exhaust. So we had the lift tied up and opted for the V band instead. It came out nice and the exhaust is made very well .