Had all the issues worked out of this machine, then...
Now no matter how many players are up, if any one has a spare going into the frame, it will only allow ONE shot instead of two! (of course a strike will correctly result in being the only shot also) and all pins will reset! This machine was working perfectly, the latest thing done to it was I straightened out a couple of the plastic pins that were slightly bent so they all would be inline. Is it even possible that a switch ABOVE the pins could result in allowing only ONE shot after a spare? Schematics attached...
Thanks!

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The spare (/) light goes out before the pins are reset.

Well...
We all know by now not to use contact cleaner or WD-40 because of how flammable those chemicals are. In fact I know firsthand after spraying contact cleaner and then turning on the machine, I had quite a little fire going in back. Luckily it was extinguished when I shut the door!
Myself, I know that the flammable part is in the carrier, which means once it dries the carrier has dissipated, evaporated and it is no longer flammable. So I did a "Bozo No-No" and used contact cleaner on the score wheel contact switches. I turnd the wheel until the switches fell into the groove where I can slide them quickly open and closed again while spraying contact cleaner. Then I moved the wheel to the next group of switches and did the same, all the way around 360 degrees. I also sprayed the rivets and fingers. I then went upstairs and had dinner for about an hour to an hour and a half, came back down and turned on the machine to play a game and lo and behold the problem was fixed! I don't know what exactly was at fault, but at this point I really don't care as I now have a fully functioning machine! Thank you all!

P.S. I don't know if I feel comfortable actually recommending anyone else do this, however.

I did very quickly move the relay plate attached to the switches on all relays, but I didn't spray.or gap them because I gapped them all properly 6 weeks ago.or so. I also tightened the 2 switch set screws on each switch set above the plastic bowling pins before going up to dinner as well. Now that I think about it before I grabbed the contact cleaner I did use the sandpaper stick on some of the relay contacts before i got side tracked by a visitor. I'll be darned if I can remember which ones though.
I think maybe I should start to take notes because I do suffer from CRS...*
P.S. I didn't clean the score reels, I clean the score motor contact switches, at least I think it's called the score motor, the one bolted to the rear door with switch sets all around the disk.
*Which in layman terms means "Can't Remember Sh**!

This is what I cleaned. I let the switch set fall in to the slot so I could quickly move all the switches back and forth while spraying.

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Then I sprayed the other side with the fingers as well as the rivets and gave it a few spins around manually with the machine turned off. Like I said it was a good hour to an hour and a half before I turned it back on so no flammable residue would be present.

I understand the risks involved with a contact cleaner. My little brother brought me some contact cleaner from work, that is non-flammable. For the life of me I had no idea where I put it! This would have been a great test to see if it cleans as well as a flammable variety. The only reason I used it for those particular switches was it seemed like it would be such a pain to remove the motor assembly to get to the switches well enough to make sure they were gapped properly and clean properly. To be honest, I did not expect it to work!

And... It Happened AGAIN!
Same issue, when a spare is showing it will only allow you one shot for the next frame. The last time contact cleaner seemed to repair it, but this time I knew I would have to clean and adjust switches around the score wheel assembly. Not the score reels, but the score motor/disc with three sets of switches mounted around it. Of course I started with a clean/adjustment of the easiest set of switches to get to, thinking I would have to pull the wheel off the door and get the rest, but lo and behold it was the first and easiest set that completed the repair! So this is something you can try if you are experiencing the same problem.