Sounds like trash in the fuel system. My truck's in the same state but I'm working on other problems now. I started it a few months ago after having not run it in 4 years.
Check to make sure it's getting gas to the carb. Make sure the carb is clean then back trace cleaning through the fuel line, pump and gas tank. Use only new fresh fuel.
Other things can cause the truck's problem but there's a good chance of it being fuel related since the truck hasn't run in years. I had to change the fuel pump on my truck. I found even though it was still working, it wasn't putting out enough. I took the cover off and found trash in a check valve and the diaphragm was cracking. New pump fixed this problem.

Jacques

Union, Justice and Confidence