Header problem

[GerryGT]

i am new to the sports car world but am learning fast. I have a 2000 gt and wanted to put an offroad x pipe and headers but was not sure which to get; hows bbk? do I put on the long tube headers and need a specific size x pipe or do i put shortie's on with a long x pipe?

any help would be great.

also what types of gains to the wheels am i looking at. I currently have pulley's, 75mm throttle body, k&n filtercharger unit, pro 5.0 shifter and 3.73 rear.

Thanks