Im currently in the process of fabricating a custom tray for my fg xr6t ute and before it goes on I will be fabricating a custom zorst for it. I have purchased a stainless xforce 4" dump and an outlaw 5" 200 cell cat. Im after advice on what way to go for muffler choice (I have absolutely no idea) pipe diameter (leaning towards 3 1/2" single with twin 3" tips) single vs twin (as above but please comment if you can offer suggestion) tips diameter etc. heres a couple of pics (SMACXR8 from A