Ruling 7-2-5
ART. 5 . . . Player formation and numbering requirements include:
a. At the snap, at least seven A players shall be on their line of scrimmage.
b. At the snap, at least five A players on their line of scrimmage must be numbered 50 to 79.
EXCEPTIONS:
1. On first, second or third down, when A sets or shifts into a scrimmage-kick formation as in 2-14-2a, the snapper may be a player numbered 1 to 49 or 80 to 99. If Team A has the snapper in the game under this exception, Team A shall have at least four players wearing numbers 50 to 79 on its line of scrimmage. The snapper in the game under this exception must be between the ends and is an ineligible forward-pass receiver during that down unless the pass is touched by B (7-5-6b).
I believe this says that that if the snapper is in under the numbering exception he is ineligible receiver.