Did you miss the write-up on the '93 fender? Fits very tight, with very little work. The only people that know its different, are kx 500 owners. You have to discourage water, mud, and i guess, road film, from pouring right in on the filter. The holes may cause some issues for you there. I even silicone the fender to the airbox, above the mud flap, to eleminate any stuff getting between the fender and air box.
I think it was Camm, that mentioned a stock fender front half, with a zip-tied straight fender on top of the OEM one, where the ties were hidden under the seat, and gave the straight fender look with all the fitment and sealing of the right fender.
I know that was some work, I tried a couple different ones before finding kxriders, 94-96 bolt up differently, 92 bolts right up, but has like 2" of fender sticking out that was originally covered by the seat. 93 is the best choice for fitment and sealing, IMO. It is easy, however, to use whatever front fender you like.