on my junk I'm using the old Holley Pro Strip Annihilator. shame they went out of production as they are such an easy to configure ignition & reliable as hell. I have a crank trigger controlling the timing & have a gutted ProComp distributor. I did have an MSD Pro Billet distributor but it was huge & had to be removed to get the rocker covers off. for just distributing the spark this Chinese POS works fine, easy to phase & small enough to allow access under the covers. the magnetic trigger inside these things is rubbish but when you not using it these work a treat & cheap!