Hey Rocky,
Just to be clear - I removed my stock air filter and used triple K&Ns. This is a HUGE improvement IMHO and should be done in order to correctly utilize any non OEM exhaust system.
Just my 2 denar worth,
1olbull
PS: I don't use the old filter box space for storage . . . at least for now.
Hmmmmmmm . . . now that I think of it; it likely would properly fit a pint or two of Gentleman Jack.