Epson EISA Desktop - Manual (Page 85)

3. Turn the coprocessor so that the orientation dot in one corner
is in the position shown below. Align the coprocessor pins
with the holes in the socket and gently push the
coprocessor into the socket, pressing evenly on all sides.
Caution
If you insert the math coprocessor in the wrong position,
you could permanently damage it.
Examine the coprocessor to be sure it is inserted all the way
into the socket.
4. Reinstall the processor board. See page 5-8.
Removing a Math Coprocessor
If you need to remove the math coprocessor from your
processor board, contact your dealer for assistance. The
procedure requires a special extracting tool, and if you try to
remove it without this tool you can easily damage it.
5-10 Installing and Removing Options