I am trying to replace an old shower stall in my basement with a new one. The old stall was made of steel. I'm having trouble removing the shower pan drain. It looks like it might be leaded in. I thought the ring that the drain cover screws into would unscrew, but it doesn't budge. The house is about 60 years old, but I'm not sure when the basement bathroom was put in. Sometime in the 60's I think. I am attaching a couple photos. Sure could use some help on this one. Thanks!
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