Fuel is undoubtedly NG unless someone put stablizer in the tank. Even then, i think the shelf life is one year. Removee the plugs and squirt a couple shots of oil in each cylinder. Leave plugs out and hook up a battery and spin the engine. Step 2, fuel it up. You might have a problem on your hands here ie a tankful of no good gas. Spray some starter fluid down the carb and see if she kicks over.If it dies when the curent gas reaches the carb, you'll have to get rid of the old gas. I'd take a couple quarts at a time and add it to my daily driver, till I can get mostly new gas in there.. Might take a little time. As far as the value...well, I'm no Chevy expert, but if it's N I C E (very nice w/ A/C and a 2 door)and someone offered you 2K I would be tickled.Good luck