With a regular old test light, see if you get a flicker on the negative side of the coil over ground while cranking and a light on the positive side over ground with just the key on.
If you have no flicker while cranking with power to the coil, disconnect the negative wire and see if the negative side sees voltage with the key on, no voltage =bad coil., if there is voltage, briefly short the negative side of the coil to ground using a jumper wire and a "scratching" motion, you should see spark. If not, bad coil. If the coil sparks, likely a bad module or ballast resistor if equipped.