I think the GVW varied, with the tires that came on the truck. I know that's true on plain old 1 ton trucks, and assume (I know, dangerous!) that the same thing happened on Panels.
That is correct.
The 8800 GVW trucks have dual wheels on the rear. I do not think any factory Panels had dual rear wheels on the rear (but, someone could have easily changed the ID plate).
