440, 487 purple shaft cam ,holley street dominator intake 750 quick fuel carb. Mopar electronic ign with chrome box with constant output regulator. Stock coil stock manifolds. What would you gap the plugs at? What would you gap the reluctor at?

.035 to .040


stock gap on the reluctor. had mine set like that for years

I would start with .035 on the spark plugs, maybe drive it awhile and then try opening it a little wider at a time until you don't like it Wider spark plug gap increases the resitance to the spark and that makes the coil make more voltage to jump the gap, which can help make more heat in the combustion chamber As far as the reluctor gap the opposite seems to work, closer is better, try(with a brass feeler gauge ONLY) .008 to .010

Good advice from Cab.
My experience is the same, but it took some learnin'. One time I planned on running the car at the strip, so I thought I'd change the plugs. I figured that HEY, if .035 is good, maybe .045 would make a wider spark! I gapped them to .045 and went to the track. It ran terrible at anything over half throttle. It popped and stumbled to an ET that was too embarrasing to take the slip! At home I regapped the plugs to .035 and went for a drive. It was better, but still not right. I checked the distributor air gap. Uhhh, .020 wasn't what the BOOK recommended! The screw allowed movement and it went from .008 to .020. Once it was back to spec, the car ran great. Too bad I didn't bring any tools to the track.