In general

For purposes of sections 3121(a)(1) and 3306(b)(1), remuneration paid to a motion picture project worker by a motion picture project employer during a calendar year shall be treated as remuneration paid with respect to employment of such worker by such employer during the calendar year. The identity of such employer for such purposes shall be determined as set forth in this section and without regard to the usual common law rules applicable in determining the employer-employee relationship.