"tightened the cap"
your symptoms are classic of a bad cap/rotor, that is if you've already replaced the spark plugs... Spark plugs and cap/rotor are made to wear out and be replaced.
Also, if you smell gas when it dies, there isn't any problems getting gas. Forget your fuel filter, pump, etc... and go after your spark.
I must ask, when was the last time you replaced the distributor cap and rotor as well as the spark plugs?