A live ball foul by B/R on a successful try or FG can be carried over to the next period, including OT, because enforcement can be from the succeeding spot. (8-3-5), (8-4-3)
However, on a foul by the opponent of the scoring team on a TD, it can not be carried over to OT because enforcement on a TD scoring play calls for enforcement from the succeeding spot- the try- or the subsequent kickoff as there is no KO in HS overtime using Fed rules. (8-2-2).
Dead ball fouls and unsportsmanlike would be enforced from the succeeding spot per 3-3-6.