tha capacitors limit and control the arcing from the points. too mush voltage is the culprit What is the coil voltage when running? should be around 9ish because it reduced from the ballast resistor or resistance wire
Well then, if you had the control box in full fwd and the drive in full fwd when you installed the drive then youmissed the roller in the slide or improperly installed the cable or improperly adjusted the cable