the carb throat is the opening under the air cleaner housing. Remove the housing and lay aside (there's a vac hose attached). Open the choke plate (which closes off the top of the throat when the engine is cold)by hand against the spring pressure, and acutate the throttle by hand (rotate the cam to which the throttle cable is attached) and watch for the squirt of fuel, about like you'd see from a kids water pistol. Remove the fuel line from fuel pump (on the side of the head between a couple of the manifold runners) to the top front of the carb. Put the line into a container to catch the fuel, and have an assistant crank the truck for 4-5 seconds and check for fuel delivery. If none, remove the fuel filter (on the dside frame rail in the engine compartment) and blow from engine side to tank side to see if it's obstructed. If you get fuel from the pump, squirt a lot of carb cleaner into the hose nipple on the carb and pray. Also remove the bowl vent hose (goes from carb to charcoal canister across the valve cover) and spray cleaner in there, too.

Past here, you really need to remove the carb and do some minor disassembly to clean it out - nothing real serious, but with some small parts that are too easy to drop with the carb in the truck.

Remove the fuel cap and smell the fuel. Does it smell like varnish, or like gasahol like at the pump?