7-2-5b: "At the snap, at least five A players on the line of scrimmage must be numbered 50-79."
Exception: "When A shifts into a scrimmage kick formation any A player numbered 1-49 or 80-99 may take the position of any A player numbered 50-79.
A player in the game under this exception must assume an initial position on his line of scrimmage between the ends and he remains an ineligible forward-pass receiver during that down unless the pass is touched by B (7-5-6b)."
I guess you're correct.
