Former Rams defensive back Johnny Johnson, now a member of the Seattle Seahawks organization, is rooting for the financially strapped L.P. Repertory in Tustin. And he is bringing former teammates with him tonight to see the current production, “The Night of January 16th,” says theater manager William Durkin. Why the interest? Johnson’s wife, Julie Gray, is playing one of the major roles in Ayn Rand’s courtroom drama. It is part of an effort to improve attendance at the dinner theater, which is about a month behind in its $8,100 monthly rent, Durkin said.