legal or not?

[sm_bbcoach]

Team A lines up for a scrimmage kick, field goal attempt, or try for point (does not matter). Ball is snapped, B53 lined up 4 yards off LOS runs takes 2 hands and pushed off of B67 who is still on all 4. The push off allows B53 to elevate up and attempt or block the kick.

Is this legal?? Only thing I can find is: 9-4-2 e which talkks about positioning himself on the sholders or body of a teammate or opponient to gain an advantage. HE has not positioned himself rather used it as leverage. I know there is a case play about hanging on the cross bar. I am looking for rule cite please.
Thanks!