Spring loaded center punches work really well to get through even tempered glass. We used them all the time when I worked ambulance and volunteer fire department.
I always liked the flat nail remover type crowbars more than the thinner bladed type ones. The nail remover type ones are wider and have a bit of a sharpened edge to more easily force into the gap. Still have a couple laying around my tool box. Leave it to a Marine to figure out what works and the Navy Corpsman to make the process better!
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