With the new cab corners in I moved to the rear part of the floor. I was a little skeptical of cutting it wrong so I made a few templates before I cut it out. I decided to make the contoured parts in the corners separate pieces I will add in later. I forgot to mention, I am eliminating the inner cab corners by doing this. Saw this idea somewhere to just extend the floor all the way into the corner instead of leaving that pocket for stuff to get trapped in. I trimmed up the floor along the back edge but left a little shelf for the new floor to sit on.
I also chose to just overlap the floor along the front edge instead of trying to butt weld the entire seam. I forgot to mention, I did the same thing on the front floor against the firewall. Just didn't want to risk cutting too much off the firewall since i couldn't get a great idea as to where exactly I needed to cut.
Im going to have to make the cab's back wall supports some feet in order to reach the floor. They were completely rusted off on the original floor.
Also grabbed a stick of 1" square tube to run a few floor supports across the bottom.