I hate playing guessing games when it comes to diagnosing a problem. The logical KISS approach would be to disconnect AND PLUG the fuel line to the carb. Set up a clean gallon can with an electric pump and plumb into carb. If it runs okay it's a fuel problem and if not an ignition problem. If a fuel problem delete the electric pump and plumb gallon can to inlet side of fuel pump; if okay then pump is eliminated and problem is with line or tank. If in ignition find someone with an engine analyzer or a Sun machine to check out distributor. Pertronix makes a stand alone distributor for about 300 bucks or an electronic conversion for around a 100 but having your distributor checked would be a first choice I'd think. The Sun machine checks just the distributor while the engine analyzer checks the cap, wire, and plugs also.
