Correct - that's a Task Force, not A/D.
The '56 specs are
online.
Curb Weight 4,595 LB. (cab and chassis)
Payload (incl "bed") 9,230.
That'll at least get you close. Wheels were changed in '56, so that might affect the figures. I've got the '55.2 manual at home.
Your GVWR should be on a plate at the front of the driver door jam. Find a set of scales near you and subtract the weight of your rig to get payload capability.
Great looking truck!
