I recently purchased a WR400F and have been doing some reading about some of the basic modifications that most owners do to their bikes. Unfortunately, the dealer I purchased my bike from hasn't been much help with my questions, which are 1) what exactly is involved in shortening the throttle stop? 2) Which after-market pipe works best, assuming one rides both off-road and MX? and 3) Does the OEM YZ426 tank, seat and rear fender work on the WR400F? Any other thoughts on modifications would appreciated as well. Thanks.