Yes there is a ballast resistor. Car has a miss/surges at a steady speed. Hard miss at higher rpm a ND hard st start after it gets up to temperature. Kinda seems like a weak coil?
Anybodys guess. That is good as any. Intermittents are difficult
Check coil voltage as well as "how solid" is the power to the ballast. Check that box is securely grounded, ACTUALLY grounded. Pull box and distributor connectors in/ out several time to scrub terminals and to "feel" for tightness.
