It's worth whatever someone will pay for it. Gbodys in good condition sell for easily up to 10 grand depending on the make, model, and options of course. Yours is very clean, nice paint, wheels, etc. I imagine if someone bought it they'd take the 4.3 and chuck it and put in a 305 or 350 because it's a direct swap so they will be buying it for the body. I'm a bit less optimistic than theoldsone here, so I'd say 3-4 grand is a good asking price. Maybe 5 on a good day if you really shined her up and had had pics of the interior and clean up and paint the engine compartment if it needs it. You can have two identical things for sale and people will ALWAYS flock to and in most cases buy the cleaner shinier one.