Thank you currieddog and Pinside! I have a 77 Big hit that has been burning through “Special When Lit” lamps. They are on the 24v circuit with 75 ohm resistors. I could see they were burning a lot brighter than all the other lamps, so I checked the resistors and they are good at 75 ohms. The voltage at the socket however is 12v. A quick Pinside search found me this thread and the answer to my problem! I am using the 47 lamps instead of 44’s. Makes sense now.

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I’m all out of new 44’s, so I went through my used bulb stash and found a couple that still look fresh. Swapped them out and problem solved! It’s a good thing I’m not much of a player, those “Special When Lit” lamps don’t get lit too often when I play anyway.

Made a note on my schematic about the lamps. And the bottom of the playfield.