How much reinforcement do you think I'd need? I was thinking diagonal bracing in the door jambs, using 1.5"X1.5"X.125" steel box beams, tying into 2"X3"X.125 steel box beams welded longitudinally along the floor, one each side. I was also thinking about a lateral brace between the tops of the front fenders at the tops of the springs, and a lateral brace behind the back seat.
I'm not too worried about the cosmetics. I can tig or braze sheet metal at the rough edges at the back to give everything a finished look.
Part of the problem here is that I enjoy welding and have run out of projects
Thanks,
Robert