Pull all the spark plugs and squirt a couple of spoonsful of oil in each cylinder. Bar the engine over by hand at least two revolutions. Put a can of carb cleaner in the gas tank, with some fresh gas. Pull the distributor and prime the engine using an electric drill. Move the throttle linkage through its arc to be sure grime and corrosion will not cause it to be stuck in the open position.
After it starts double check the timing and let the engine come up to stabilized operating temperature before you shut it down. Then change the oil and filter, and maybe flush the cooling system.
Also check point gap / dwell, plug gaps and spark plug resistance. And look for signs of damage by rodents, wasp nests etc. Good luck.
