NEC POWERMATE P - SERVICE MANUAL 1996 Service And Reference Manual page 100

3-32 Option Installation
4. Insert the device into the device slot from the front of the system unit, connector
end first.
Secure the device as follows:
5.
n
If installing the device into the top 5 1/4-inch slot, align the holes in the device
with the holes in the device cage.
Secure the device with the four screws that come with the device, two to a
side (see Figure Section 3-25 and Figure Section 3-26).
n
If installing a device with rails in the middle or bottom 5 1/4-inch slot, secure
the device with the two screws that were removed during slot cover removal
(see Removing the Front Panel and Figure Section 3-25).
Figure Section 3-24 Attaching the Device Rails