I have a 97 GTP, 180 T-stat, K&N CAI, Intense PCM Stage 1, Intense 3.4 pulley, Gatorback belt, 99+ Coolant Bottle, autolite 104s, PRJ Wires, Thrasher Shift kit, Tranny Cooler, Hurst Hit Shift Fluid, 17" TSW Eurace Wheels w/ Potenza Tires, TOG Headers with DEI Exhaust Wrap. My Plain is to do stainless Steel 3" piping, remove CAT, Resignator and U-Bend, go straight back to Y, and Dual MagnaFlow Mufflers, will these be OK now and with my new engine currently being built which will be well over 400 horses?