I wouldn't give more than a couple hundred bucks for it. I am not trying to pee on your parade, but what you can see from the outside is just that. Usually, once you dig into it, the damage is worse. It's not at all hopeless, but there is some work there.
The bright side is there are good parts on there. Depending on your plan, you can sell those unwanted parts and easily pay for the truck. The windshield crank itself is worth quite a bit. That truck is just a little worse than the free '40 Chevy cab that I started with. I chopped it and sold the cab and doors alone for $600. I sold unwanted parts off of the '40 GMC I am currently working on and actually made money!
Good luck!