I got you on this one mate,
These locks have 3 spools in the rear 3 chambers with a standard M1 keyway.
The plug is spring loaded so using that is your advantage.
Take a thick tensioner and crank the tension. Lift one pin at a time, while lifting decrease tension enough only to lift the pin with out damaging your hook.
Once the sheer is caught, crank the tension again. And repeat 3 more times and it shoudl open, practice it 5 minutes and they all fall open in under 30 seconds.
The spring poaded plug throws everyone off, but there a sinch.
Glad to see another pennsyvainian in here
Good luck mate.
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