The tubing is 2" X 2" outside diameter, 11 gauge, about 1/8" thick. On my site under Body Jig you will see how I welded up the washers where the body mounts bolt on. When I built this jig I had the body, front fenders, grille, the chassis had the engine and transmission in it, in other words most of the weight of the car body and all the components was on the car. The car set really nice and straight, so I built the jig to fit this car. I plumb bobbed from the center of all the body mounts to the garage floor. I plumb bobbed four other points on the frame to the floor also. I used threaded rod with long nuts and a post level to get the height of the body mount to the garage floor. The last two pictures in this series shows the plumb bob and the threaded rod. I guess the good thing about showing these dimensions is it will give someone a rough starting point on how much steel and an idea of how it can be done. Once you get the measurements from the floor to the body mounts, then just add a foot or two to all the uprights and you can make it as high as you want to. If you keep it about the height I have it, you can get under there with a body creeper and you have room to work.