Bennett pump doors. Sight Glass/Trim holes at the top are filled in. I'm told that's factory and with lead?

Any of you restorers dealt with this? Can it be melted out with a propane/MAPPS torch? Sorry I didn't take a pic of the inside. There's a piece of metal 'welded' to the back but not like mig-welded.

Also, difference(s) between a 966 and 1066? Did some digging but couldn't determine that.

Thanks!

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