If the floor from the seat riser to the back of the cab is not shot, you can buy the front floor board halves patch panels and and cab supports, and make your repairs one side at a time without any bracing on the frame. I have done it before on a true basket case.
Since you seem to not own a welder or know someone who will do the welding for you, you may well be over your head on this project.
I know that I was in over my head on my basket case, but with undaunted perseverance and the wonderful folks on this site to steer me along, I was able to pull it off.
