I was thinking twin 2 1/4 from cats to y pipe then either a 2 3/4 or 3 with a 2 3/4 or 3"inlet/outlet muffler then into a another muffler that has twin 2 1/4 outlets then have 2 pipes running to the rear bar, because i am going to make it myself so i'd rather not have twin pipes all the way through