Reporting Eligible Numbers

If have an offensive lineman (#53) that I would like to hand the ball off to on the goal line, does he need to have an eligible number, does he need to report to officials before coming in, or is he fine as long as he lines up in the backfield?

By NFHS Rule 7, Section 3, if #53 is lined up as a back, he may receive a handoff behind the line of scrimmage. There is no reporting procedure in NFHS rules.