To install the chips, first you should back up your current settings using your old version of CMK config.
Make sure the power is off.
You need to remove the 2 screws that hold the circuit board to the keyboards. There will be 2 sets of ribbon connectors. One set is right at the front and one is further back. Ease both of those off their mounts.
Look for the chip the same size as the replacement one. Note the little semi-circular cutout at one end of the chip. Remember which way it was situated.
Ease out the old chip from the socket.
Gently but firmly seat the new chip in the holes with the semi-circular cutout pointing the correct direction and press down until it is flat.
Reconnect both sets of ribbon cables.
Replace the screws.
Repeat this with each of the CMK-2 keyboards.
Once you have replaced the chips, you can connect the two older keyboards together and load in the old backup with the new CMK config. Remember to plug in the MIDI in and out into the computer while configuring.
Then you can hook all the keyboards together and use the "load configuration from CMK". Find your backup file that you saved at the beginning.
Press the Lightning bolt icon to save the configuration back into the memory of the keyboards.
Disconnect the MIDI out from the computer and you can start up Hauptwerk.