Earlybird: I have two spare sets. one is a 52-53 series, the other a 56-57 series. What is the number stamped on the rear face of the cam?

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2021 Charger Scat Pack Widebody "Sinabee"
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1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k