While in that mix are two excellent choices, I have to throw in a pitch...Snellerized, one of the actual innovators. Of course that's if he actually has time. Lots of good ones, just I remember the conversations years back, and the ones who came later to the mod party, LOTS have come and gone, and now more than ever there are folks trying to break into the world as the "practices" are pretty established. Compression, Timing, Porting....Tree Monkey another true innovator. I can't remember the fellow up in Ontario who was also on the bleeding edge. Lots of what is now "common" was worked out years back and its more about marketing and craftsmanship differentiating the ones really active now. Just my most humble opinion.