Illegal Formation - NFL Rule Question

[tmref]

It is a foul at the snap as MJT stated. However, an ineligible player may take an eligible position or an eligible player may take an ineligible position as long as he reports to the referee before the play. The latter most often happens on punts when the long snapper is wearing an eligible number.

[golfnref]

Originally Posted by tmref

It is a foul at the snap as MJT stated. However, an ineligible player may take an eligible position or an eligible player may take an ineligible position as long as he reports to the referee before the play. The latter most often happens on punts when the long snapper is wearing an eligible number.

We finally have the correct answer to the original question. NFL Rule 7.2.3