I used a baggy and a small cup to soak the whole part with the leaves in the Pb Blaster. I soaked it for over an hour total. I took it out from time to time to try to work the leaves loose one at a time and blow it out with compressed air. I cleaned one leaf with a scrubbie pad but maybe didn't get it clean enough to see numbers if they were there.

I have tried to collect some books on locksmithing but they weren't cheap when I looked.

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