Equinox Systems MEGAPLEX Hardware Reference Manual page 15

Figure 2-3. Installing MEGAPLEX host controller in a tower chassis
6. After making sure that the top of the board's bracket is
aligned with the hole on the top of the expansion slot,
replace the screw which previously held the expansion slot
cover. Tighten the screw firmly so that it holds the board in
place.
7. If more than one MEGAPLEX host controller board is to be
installed, proceed to the paragraph heading Installing
Additional MEGAPLEX Boards.
8. Leave the cover of the computer off until you verify that the
board is working properly. This makes it easier to check the
board's seating if a loose connection or a bad slot is later
suspected.
Installing MEGAPLEX Hardware 9