from your description its sounds like you have a gm HEI distributor......they are notorious for burning out the rotor, try a new one before you buy anything else

And if that does not work then its the module. With me its alway been the module that failed giving  no spark.

On my '85 Celebrity ... i was getting cross talk on the two thin wires from the module. Separating them let the car start normally. The insulation had dried out.

Check both wires on the pickup coil, the piece with 8 pointed tabs on it. I think the wires are green and yellow on an OEM unit. Often the wire breaks right at the point where it goes into the unit.

I have a good way to check the pick-up coil or module. First take off the cap and lay it upside down, take the wire connector off the module from the pick up coil. turn on the ignition. Take a test light hook it up to battery positive  and hold it to the carbon button in the cap ( the part that contacts the rotor). Then take your fingers and touch the two terminals on the module where the pick up coil was hooked up to, you should see the test light each time you touch the module. What you are doing is taking the place of the pick up coil, you have enough continuity in your fingers to do this ( you will not get a shock I hope ! ) This is a quick way to determine if the pick up coil or the module is working ok. It has been a while since I have done this so I am not sure if you hook it up to battery positive or to ground  (pretty sure it is battery positive ) I have used this  procedure many time to eliminate a bad pick up coil or a module!

Kevin

if i was you i would start by swaping wires then move on to fues then move onto replacing parts Oh and check everything with a volt meter to see where the problem is coming from =)