Key stop rail. There are screws holding it in place, on at each end and a support screw, post, bolt or something in the center. It is remotely possible that it is glued and screwed ot the key blocks and will have to come out with the blocks. I have seen this arrangement but never on a Baldwin product, too complicated and difficult to do. Germans do it and I have seen an English birdcage that way. Look and feel carefully, there should be screws there. I did see one piano where it was slid into place on two dados, one at each end. Now that took me a few to find but again too expensive and hard to do for a B. Look again. Newton
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