Finish tuning your bow.
1) shoot a field point tipped arrow into the bulls eyes
2) shoot a broadhead tipped into aiming at the same spot.
3) move the rest away from the broadheads impact. ie - if the arrow is high right, move the rest dow, left. You can also move the nock point, but make it follow the arrow. ie - high arrow = raise nock point
4) repeat step 1 and 2
5) after #4, if the broadheads and field points dont group together, repeat step 3
6) after you get the field points and broadheads grouping together, adjust your sight to bring them both back into the bull.

I would be willing to bet if you got the larger diameter heads grouping with your field points, the smaller ones will also.