Surgery was a success! It almost wasn't because the black scales appeared to be glued in place. I asked Sencut if the scales were glued and they said no. So I wondered if someone at the factory had just gone nuts with the thread-locking compound.
I freed the scales by soaking in near-boiling soapy water for a while and then pushing the hardware through with a punch. My suspicion was correct. The gummy residue on the threads was spread out to about the size of a quarter around each of the screw holes. I quickly removed it with a little copper wool and I was back in business.
I'm happy with how these turned out.