Let's assume all the things you have listed in your "have done" list are correct. Some Barners are suggesting you check your wiring and key switch. I agree this could be an area where there is a problem. Rather than troubleshooting the wiring in an effort to prove your engine runs I would bypass the wiring and do the following:
1. Assuming your wiring is (+) ground leave the wire connected to the (+) pole on the coil connected. This wire should be connected to the points in the distributor.
2. Remove the (-) wire on the (-) pole of the coil. Connect one end of a temporary 20" long jumper wire to the (-) pole on coil. Attach a single throw toggle switch to the opposite end of this wire. This will temporarily replace your key switch.
3. Take another piece of wire and attach it to the opposite post on the toggle switch.
4. Connect the other end of this wire to the starter motor cable connection.
Turn ON the toggle switch and try starting your engine. If it starts your problem is somewhere in the wiring.