Epson EL 486UC - Manual (Page 61)

2. Remove the two retaining screws securing the option card
connector board to the back of the computer, as shown
below.
3. Pull the board straight up and out of its socket and set it
aside.
Replacing the Option Card Connector Board
If you removed the option card connector board, follow these
steps to replace it. Refer to the option card connector board
illustration above.
3-18 Installing and Removing Options