Pianotech

I have a Steger and Sons grand piano. I cannot find a way to remove the fallboard. I removed the keyslip. There were no screws under the cheek blocks on the bottom. There were no screws on the side of the cheek block near the keys 1 or 88 horizontally where they sometimes hide. There was a black button on the top of each block and I removed it. No screws. The legs were like a Steinway lyre and I could knock them out. There were no screws under the legs. There were many blank holes and I tried every one of them to look for a screw with a screwdriver and a flashlight and different screwdriver widths. I looked on the left and right of the frame in case someone drove screws into it from the outside. There weren't any. I assumed the screws on each side going through the upstop rail were going down into the cheek block and then down into the bottom. The fallboard wouldn't give me enough space when I pulled it down to get an offset screwdriver under (barely any space between the fallboard and rail) I used some pressure and pried up the block in the front enough to shine a flashlight to see if I could see a shimmer of a metal screw instead of a dowel in the back. I saw a small reflection. I'm assuming it's a screw. I tried to pull up the fallboard to pull it out with the cheek blocks in case it was a down and it wouldn't budge. If it was swollen from humidity in the dowel in the back of the block then it was stuck, but I'm pretty sure it's screws. The stretcher is attached to the plate and I don't want to remove it, but even if I did, it wouldn't be possible to get a screwdriver to where the screws would be since the fallboard is covering it even when it's down. The only way I can see is to dislodge the pins inside the hinges facing the front that are attached to the fallboard and the rail. The customer does not want me to damage the wood. Any other ideas PLEASE. I plan to replace the hinges with new ones and change the screw to only attach to the top half of the cheek block and then drill into the bottom to put a new screw in so it holds it from the bottom instead, and maybe even put in a dowel in the back afterwards, but I can't get in. How can this happen? 

I agree with Wim and Nathan. I've seen this design many times and it's simple once you know what to look for. 

In the off-chance that this solution doesn't work, could you post pictures of the front of the piano, the sides of the fallboard, the fallboard hinges, the cheekblocks, and the underside of the key bed? Those might help us narrow down other possible solutions with you. 

I had one of these several years ago. They're beautifully constructed Pianos. You have to remove the stretcher. The stretcher is attached by screws passing through the plate into the stretcher.