Back in the interior, the relocation point for the rear seatbelt mount that was center-punched earlier was drilled out to 11/42 inch. The supplied seatbelt bolt mount was then positioned over the hole and traced. Four 91/432 holes spaced 90 degrees apart were drilled inside the marked perimeter. While using a bolt to hold the seatbelt mount to the underside of the floorpan, the holes were plug-welded, then ground flat. Finally, the mount was welded to the bottom of the floorplan and the bolt was removed. The entire tub install procedure was repeated on the other side of the car.