I've been thinking of your problem and would like to take an analytical approach to it.
I would ignore the codes for now. (They could be the result of the initial problem and the backfire)
I'm sure you did a visual check of the vacuum lines and wiring and such. Also check the battery connections at the battery and starter and solenoid. especially the grounds. Since you had the solenoid seize I'm thinking there may be an issue with connections.
If they are all ok try the following checks in order:
1- check that #1 is indeed at TDC of the intake stroke. (your systems sound like a timing issue with it being 180 out......How, we will address after we find out )
assuming the timing is ok:
2-connect a test light between the + and - terminals on the coil. ( they HAVE to be connected at the coil for a proper test) Verify 12v at the + side with the key on. Crank the engine and watch for a flash of the test light in a good rhythm with the cranking speed.
If the light flashes with good rhythm. assume the primary circuit is good and the coil is getting a proper "fire" signal. If not the problem is in the primary ignition system and could be poor grounding that isn't transferred through the ICM to the coil. Or a bad ICM or Dist. pick up, or wiring to the same. Remove the dist cap, disconnect the + wire from the coil for safety and crank the engine. Observe the rotor. Is it turning in rhythm with the engine? If it is move to 3. If not, the dist gear or cam gear or timing chain is the problem.
3- If primary ignition circuit and dist is good, reconnect the cap and coil primary wire. Disconnect the secondary coil wire at the dist. carefully hold it close to a ground and crank the engine. Check spark. Good strong spark in a good rhythm to the engine cranking clears the coil. Not good= malfunctioning coil.
4- if coil is good, reconnect the wire and do the same check at #1 plug. Repeat for all other wires. If all is good, pull the plugs and observe. Shake and turn each with electrode down. ( I had found plugs that had broken electrodes that would be pushed up into place under the compression stroke only to fall down against the ground during the power stroke and cause a miss. looking at the plug upside down showed no problem. I know bizarre, but its worth the check. ) If all is good, you can eliminate the ignition system as being the problem.
Post results here and we will move on. I know its tedious, but its good to know what isn't the problem and eliminate them rather than "shoot in the dark"