"Remanufactured" carburetors and distributors (and starters, and alternators, and...) tend to be junk. Exactly what carb did you buy, and from where? "No air/fuel adjustments" is wrong right off the bat; all carbs have air/fuel adjustments -- if yours doesn't, something's wrong.

Cancel that order for the "rebuilt" distributor. Don't just buy and toss on parts at random.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Holley 1 Barrel 1945

Rockauto- AUTOLINE C7386 Holley 1 Barrel 1945

Rockauto- A-1 CARDONE 303691 Dual Pickup; without Vacuum

Yup, "remanufactured" junk.

Since we're talking about a dual-pickup distributor, it means you've got the Lean Burn system, which is notorious for breaking down over the years (remember how old this truck is) and causing poor running. You've got some decisions to make; your best way forward is probably to ditch the Lean Burn and put in HEI with an appropriate carburetor.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.