Does it still have the original points-type distributor in it? You can check to see if current is getting to your coil by probing the + terminal with a test light. While cranking it the light should turn on and off as the points "break and make".
The coil for a points-type distributor has two hot leads going to the + terminal. One coming from the ignition switch and the other coming from the "R" terminal on the starter solenoid. During cranking the coil is fed by the wire going to the solenoid as that wire provides a full 12 volts. Then once it fires off and the key is returned to the "RUN" position the coil gets fed 6 volts by the braided resistor wire going to the ignition switch.
You say you replaced the "ignition" switch that is mounted on top of the steering column right next to the firewall? That switch has slotted adjustment holes in it's base and must be "timed" so it's fully engaged when the key is rotated all the way foreword.