I called Wilwood and the sales associate said the kit is designed to work with OE equipment so go for it. He didn't think there would be any issues. I guess I can put a 1/2" bolt through the hole and put a lug nut on it and see if it even seats very well. I am certainly not going to upgrade my wheels to large bolt pattern and still use this kit. It wouldn't make any sense.
I'd be careful with that advice from a sales assocaite....easy to say 'go for it' if it is not your stuff; that individual may well not know crap about mechanical work and proper wheel fit, etc. Never trust such off-the-cuff info, IMO....
I would try to find, or ask for, the manufactured hole diameter for the wheel studs. For standard 7/16" wheel studs, the holes should be somewhat smaller than .565" ID. Of course, if you already have this kit, then proceed with a fit up and see; the issue is the taper in the lug nut not seating deeply into the matching taper in the wheel holes.