This mod was already done to the bike when I got it but is easily (and cheaply) done. All you need is a Round Tapered Cone Filter from here
and a 90° bend stainless steel braided car radiator hose (get at any speed shop) and a couple of hose clamps. You need to fabricate a frame mount out of 1/4" steel (or whatever you have laying around that will hold up the whole thing) and your in business!
I will give you the diameter of the hose and K&N pod used on my '92 vt600c when I have time to take it all apart. I'm not sure if it would be the same size as yours since the diameter of the airbox hole may be different on different bikes. NOTE: The airbox hole is oblong making inserting the hose a little difficult, not too bad in my opinion since it's airtight.