Help on my 440 Duster

Id first verify that your getting spark in the "start" position. Pull number 1 plug out and hook it up to the wire and lay it where you can see it from in the car. Then go crank it over and make sure its sparking. If it is, then whats your timing set at and how is your carb baselined and what carb is it? if not, Id investigate as to why its not sparking while cranking.