Bite the bullet and buy them. I felt the same way about buying beach wheels ($400 -$500), but I finally ponied up the cash and could kick myself for not doing it years earlier. I have 3 friends who sail H14Turbos, all with hydrofoils, and they can drive the boats much harder with less consequences. They will not save you always, but they do increase the margine of error (and face it, we could all use bigger margins). To drill the holes tape the hydrofoil in place and drill up through the hydrofoil hole. Insert the bolt from above. You will notice the bolt head will not be flush with the deck. We used a very small amount of Bondo (epoxy would work also) to fill the gap under the front of the bolt head (bolt inserted all the way in, but not tightened) and let cure, then we tightened the bolt (do not over tighten).