I picked up some large megaflow tips and then cut the pro 1 covers in half, sliped the megaflow over the pro 1 and they look great. The tips have 4 inch inlet and come out at 5 inch. You just have to cut off about 4 inches off of both covers. Work is still in progress and I will post some pic's as soon as I am done. You can adjust them the way you like after you have cut them. But the megaflow tips are around 85 bucks each. But they are well worth the money after you do the work..
Try this link
Buy MagnaFlow Performance Exhaust Online
and the part number is 35148 MF-Performance.com MAGNAFLOW TIPS
Hopes this helps you as it did me... Good luck..
http://www.mf-performance.com/02prod...=main&id=11430