Applied Engineering Sirius IIGS User Manual page 21

If you want the card to appear to be in the slot in which it is
installed, set switch 4 to Open. Switch 2 can be Open or
Closed.
11)Insert Card Into Slot
Align the gold "fingers" of the controller cards edge connector
with the slot; then use the heel of one hand to push the card
down into the slot and seat it firmly.
12)Connect Cable from Vulcan to Controller Card
Attach the wide flat cable from the hard drive to the connector
on the controller card. The connector and socket are keyed so
that they will attach in only one way.
Make sure that the cable connector is firmly seated in the
controller card socket.
13)ReInstall Any Cards Removed
Replace any cards you have removed for the installation
following those cards' installation instructions.
*
14 Vulcan
Insert Controller Card into Slot
WARNING! IF YOU HAVE A CARD IN SLOT 1, use
the insulator card (2" x 6") included with the Vulcan
package. Applied Engineering will not be responsible
for damage to any other products so be careful when
reinstalling your cards.