Replacing the soundboard in a Steinway D

Here's a couple of pix showing the size of the soundboard, and the new board as a mirror image of the old one. The high treble section of this board is morticed into the rim. Although I have seen a few other makes with this feature, I have never seen it in a Steinway Grand. If someone out there has , I would like to discuss the methods that they used for removal and installation of the new board. The pinblock was also morticed into the treble end of the Rim.