Just a few ideas.....Do you have another distributor and/or coil (check compatibility) you could adapt & try? I recall hearing that the Uni-lite distributors can go bad, but don't recall the symptoms. (Dirty window?) Gotta ask - firing order correct or timing moved? I've run a Malloryr 6AL with one of their magnetic pick-up distributors for 15+ years with no issues.

EDIT - I did have one issue: One of the pins in the distributor lead pushed back in the plug and had an intermittent connection.