Apple PC Compatibility Card (Installation) - Manual (Page 42)

3 While supporting the adapter fence with one hand, push the card until it snaps into place.
Don’t force the card. If you meet resistance, pull it out and try again.
4 Reinsert the screw into the PC Compatibility card fence and screw it into place.
To help insert the screw, push the card fence forward with your thumb so the
screw holes align. Insert the screw until it’s somewhat steady, hold your thumb
underneath it (to prevent it from falling), and use the screwdriver to tighten it.
You may find it helpful to
support the screw with the
thumb of your other hand.
Adapter fence
Card fence
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