1. Before pulling the column apart further, I would check to make sure the ignition rod is moving with the ignition cylinder. If you pull the two panels below the steering column and reach around from the left side you should feel two rods on top of the column (they come out from the outer collar just behind the gauge bezel): one at about the 10/11 o'clock position for the high beams, and another at the 12 o'clock position for the ignition switch. When you turn the key, you should feel the ignition rod slide down towards the firewall.
If it doesn't move, then you've probably found the culprit, and will need to tear down the upper column.
If it does move, then the ignition cylinder is fine, and your issue is elsewhere.
2. You said after checking the fuses that the dash has lost power but the horn and interior light still work, what about the headlights and brake lights? If those don't work, I'd say try running a 10-12 gauge test wire from the positive battery terminal to the junction block on the firewall next to your brake booster, that should bypass most of the fusible links. If power is restored, you have a bad link. If not, at least you can rule that out. There might be more links between that junction block and the fusebox, but to check that you'll probably need a wiring diagram.
3. The ignition switch might be slightly out of place or the rod may not be engaging the switch properly. If you can get the switch down without unplugging it you can stick a flat screwdriver in the slot for the rod and push it back and forth to see if that works.
