Start with the basics,I had a simular problem with mine . I had not run the truck for a few years and it was running rough.so I changed the points and the newer style points seemed to have a extra metal spring with I thougot was for other applications as there was a brass spring already part of the points .after install the truck ran great. StarTed to drive and would backfire and miss seemed starved for fuel. Left the truck until the next year,tried carb rebuild coil and fuel pump,was told by a old time mechanic to start with the basics .that extra metal piece from the points was the problem as the truck reved up the points would bounce and needed the extra spring to put pressure on the points to snap it back as the rotor turned .was a silly problem that drove me crazy.but I learned from the old timer to start with the basics.
