Diagnosing Distributor - No Spark Chase

perko said

I've noticed that I get 12 volts at both the positive and negative terminals of the coil when the ignition is in run. when it is in crank the light is a little duller but appears to be the same at both terminals. Is this normal? Also, there is no spark coming from the coil which bench tested ok.

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Yes and no.
With the coil not grounded on the (-) side; The test light should be brighter on crank than on run, and the crank voltage to the coil should be near battery voltage, while in run it should be down at about 60% of battery voltage...... but you will have to wait for the ballast to get hot to measure the final voltage. Recall that this is with the coil (-) disconnected, and open circuit, so the ballast will not get got. You will have to pull some amps thru it to warm it up.
With the coil (-) open circuit, both sides of the coil will read similarly but not the same, because the MOPAR coil primary side is just a really long thin wire spooled up inside the canister. This is not true with an old GM coil, which looks the same but may have the ballast internal. These coils are usually stenciled with I forget the wording, maybe " not for use with external resistor", or something that means the same. If you have a Mopar, you gotta use a Mopar-specific coil.