Talk about cashing in: Identical-twin actor-filmmakers Mark and Michael Polish (”Twin Falls Idaho”), who portray casino workers opposite Nick Nolte in the heist flick ”The Good Thief” (opening April 2), used that connection to wrangle the actor for a role in ”Northfork,” their upcoming low-budget absurdist drama. ?We became good allies because of our view of indie film,? says Mark, ?and Nick asked if there was a part for him.? Mark promptly cast him as a priest who aids a dying boy, but there was one problem: Nolte was committed to Ang Lee?s ”Hulk.” ?Thanks to that monster movie and our conflicting schedules, trying to get him was tough,? Mark says. ?We eventually made our deal on a napkin, and it got to the point where his assistant was faxing me Nick?s [wardrobe] sizes from the ‘Hulk’ set.? There shouldn?t be as many snags on the Polishes? next project: the sci-fi flick ”ID,” which they hope to make this fall for Warner Bros.