This may be a partial answer to your question. I do not recall seeing any pliars to squeeze key leads but the pliars known as shank knurling pliars, APSCO #15194 on page 17 of their catalog will do a fine job of squeezing damper underlever leads tight. They will not touch the wood as they apply pressure on the lead but you must be careful to not apply any twist of the wrist to damage the action center. Norm Barrett Memphis, TN
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