In prepration for the floor we installed the cross braces and also insered the inner rocker panels. I was able to use the dimensions on the frame to layout the cross braces since two of them have body bolts going to them. Another trick I started using at this point in the project instead of the cleko's were sheet metal screws. They are stronger and easier nearly as easy to put in, they also provide a nice size for plug welds.
This is the new floor including the toe boards which required a bit of work since the entire area at the bottom of the firewall was missing.
The piture speaks for itself. The new floor is in and overall fit quite well and I think the best thing is that it's a one-piece item so it really makes life easy when you do have to replace the entire floor. I did have to use a strap to bring the width of the body at the rocker panels together to the point where it was consistent. Other than that it went together much easier than I expected. I think the key was replacing the entire floor including braces and rocker panels, this simplified the work.