There has to be a shop in your area that doesn't mind the old iron. For plugs I swapped to regular Bosch platinums - lasted years as opposed to champions. The regular mopar system works just fine and is pretty dependable, you must have something off there. The low voltage may be an indicator. If you have a newer electronic distributor they have an adjustable advance, try backing it way out but not all the way. I'm wondering if your advance is off and its keeping the carb out of the idle circuit and the carb is just dumping...