Disconnect the wiring coming off the DM board to the main chassis. On this TV there were four separate wiring harnesses: DA,VA,DB and PF. These markings are not of importance to this repair. But they all are clearly marked on the connectors as well as the logic board they connect to. This will help to identify their proper position for the re-assembly.
Undo the two screws that hold the plastic cover to the DM board.