So, I pulled out the carpet in the trunk of my D1 to start work on my new cargo area storage. Needless to say, I found a butt load of rust. At least 1/3 of the seam between the center floor and the body was rusted through. The rest was showing tons of surface rust. I figured it would be dumb to build a nice new cargo area on top of a bunch of rust. I decided to replace the bad metal. I started by drilling out the spot welds. Unfortunately a good portion was too rusted to save. I ended up having to cut the whole thing out, including the supports. I then picked up a sheet of .78 galvanized steel. I had it cut to fit and then bent a 1/4in lip on one end. The bent end will be towards the rear of the truck because I had to cut the lip that the original sheet was spot welded to all the way around. I made my cut at the high point of the floor. The rear most lip is 1/4 lower. As of this moment I have it all in place and tacked in a couple places. I'm going to finish welding it in tomorrow morning. I'm going to seam seal it, then cover it with Dynamat before building my new storage. I also had to move the brake hard lines because they originally ran through one of the floor supports. They now terminate on the passenger side frame rail.