2x3" tubing will have to go through the floor at the rear pan; 2x2 will fit beneath it. It is a straight shot from the torsion bar mount to the rear frame rails. We cut the diagional section off the rear frame rail and slipped the tubing inside it. You can drill a 1" hole in the frame rail and weld a rosette weld to the connector and along the diagional section of the frame rail. It will be plenty strong.