The cheapest and one of the most reliable solutions, is to adapt the original distributor to a Pertronix electronic ignition, which is under $70 bucks. I have never had another problem with it!
And yes, the Holley/Webbers are the Pinto carbs. I've got one too, and I'm a lot happier with it than the old 1 bbl. How well does the twin carb, 4 bbl set up work on the 235...when the ignition is working?