Hi JD If the existing pins are 7.20 mm then they have been changed once already. And if only once then the jump up from the factory installed 6.9 was a fairly large one. I'd be a bit cautious about a 1958 B that has had such a change once already and now needs bigger pins. Get your fellow in South America to check the torque on the pins. If they are good I'd suggest to use the existing pins instead of changing again. If they are loose already... I'd have to be a bit suspicious about the block, piano unseen as it were. Cheers RicB
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