I will have the following setup and upon it i ask the question of whether i can modify a 2.5"inlet/3.0" outlet y-pipe....2.25 inch outlet headers...2.25 inlet/2.5 outlet test pipes...2.5 inlet/3.0 oulet y-pipe which will be installed on the stock exhaust..now i want to modify the outlet of the y-pipe to match the 2.5" inlet of the exhaust..has anyone done this? And will it work?