No fire

[38 coupe]

Before installing an unknown distributor and coil I like to bench test. My setup is a bit ghetto, with a spark plug gently c-clamped onto a distributor ear and a wire with alligator clips going from a rotor tang to the top of the plug, but it gets the job done. Occasionally I find a combo that doesn't spark and go through the normal troubleshooting steps common to points, coils, and condensers.
FYI, have you tried swapping in the old condenser that was working?