we are getting Dual 6" Turnouts only cause that is the only kind our truck supplier had the dang big. should we have to worry bout Black rain. i dont think so. we are going with the box setup in the bed a 10in X10 in box in the bed four inch from the turbo into the bed 4 in then out of the stacks 6 in. sure hope she sounds sweet. BTW no mufflers will be installed.