I bolted up the lower cross peice today (3" x 3/8" Aluminum plate) that the y drive nut will mount to and added the lower X pipe. I set the rollers on the x pipes and used the calipers to deturmine the distance of the assembly.
I made the Y pipes as wide and long as the table would allow then matched the gantry to this width. Now the X assembly will be built to match it and the Y to match that. This way I get the biggest machine that I can fit on the table and not have to try and draw plans for it.
I got the y rails level and parallel. It slides much smoother than I would ever had thought. The lower cross bar makes it a lot more rigid.