Hopefully you will be able to tune it to shoot off the shelf. I once had a Hoyt Gamemaster II that I couldn't tune to shoot off the shelf. The bare shafts would nosedive into the ground, even when the nock point was set at zero. The bare shafts flew fine from a rest about 1/2" above the shelf. I even tried reversing the limbs, in case they were marked wrong, but no go. Since I only like to shoot my bows off the shelf, I eventually sold that bow to someone who wanted to shoot from the rest. It's possible that someone who didn't bare shaft tune might not have minded, as the fletched arrows seemed to fly okay from the shelf, but I wasn't happy with it, knowing that the bare shafts wouldn't fly well from the shelf.
The same sort of thing is true in trying to re-tune a bow tillered for split fingers for 3 under. Most of the time, they will retune okay, but there is the occasional bow that won't.