Epson Progression U12 - Manual (Page 100)

2. The daughterboard has two sockets which fit over two of the
four pin connectors on the main system board (the two
closest to the back panel). To remove the daughterboard,
carefully lift up the socketed end of the board to release it
as shown in the following illustration. Then remove the
board from the computer and set it aside.
Wrap the old board in an anti-static bag and store it in a safe
place in case you need it later.
Installing and Removing Options 3-31