Remove the melody side, (right hand), keyboard cover. Most are fastened with either 3 or 4 screws or "pins" that pull out. Once the screws, (or pins), have been removed, the cover should come off easily. The keyboard should now lift off. (Those that used "pins" will have the keyboard screwed on with about 8 screws.) Air pressure from the bellows may be used to "assist" with keyboard removal. Be careful not to damage the bellow gasket. Do not remove reed plates. Count the number of reeds that are mounted on the outside surface of the reed plates.These are the reeds that sound in 'Press'. (There is an equal number of reeds on the inside surface for 'Draw'.) Divide the number of reeds on the outside surface by the number of buttons on the melody side. The result will be 2 for a 'Double', 3 for a 'Triple', or 4 for a 'Quad'. Not all of the reeds will have 'leathers' on them. When reassembling the concertina be careful not to get any of the reed leathers caught on the bellow frame. The keyboards that were made in the "pre plywood days" are very fragile and crack easily. Set the cover loosely on top of the keyboard and line up the buttons with their respective holes with a toothpick, hairpin or something similiar. Install the air valve cable. (If the air valve cable has a leather washer it goes underneath the air lever.) Sometimes reaching through an adjacent hole will help to align the buttons. Do not over tighten the cover or keyboard mounting screws.