width between pillars?

[Paneleer]

I have the panel truck, the pillars are rusted but received a not-so-good repair in a previous life, what is the correct width of the pillars where they meet the front floor?

I measure out 56 inches between the pillars, and there is a slight drop, the bracing installed must have been to hold the roof up.....

see...

and here too

[JBNeal]

http://dodgepilothouseclub.org/know/blueprints/index.htm