Take all the old strings off, clean up and then restring. Put the piano on it's back if you have a tilt truck. It should take the equivalent of two tunings to get the strings on and pulled up to near pitch. Figure tuning them four times before you leave. The rest of stability will occur over a period of months. Figure in one return call to retune the strings. Now, the questions is, how is this piano being played to have so many broken strings. I had 49 Yamahas at the university from that same era and not more than two broken strings in the nine years I was there. You might consider deregulating the action to reduce the power. Shorten blow distance, shorten dip and set the let-off at 1/4" instead of 1/8" and have the church put a monitor speaker with the volume set high right at the players ear level. That helps a lot! Newton
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