Competition werkes makes a kit for the 'Busa you can get it at Lockhart phillips. Also Mototeck has an undertray/fender eliminator for it as well.
I went to the Muzzy's site and looked at their photo's of the stock fender trimmed, did it to my own as well as redrilling the liscence plate hanger holes and shimming them with washers.
Looks good enough for my ninja riding friend to want me to trim his!
I did mine myself. It tooks a good night's worth of work, but it looks factory. I used the original signals by cutting into the sides and mounting them on the inner wall support. The cut was finished by sanding then heat treating the plastic, so you can not see where it was cut (or that it was cut at all).