Apple LaserWriter 12/640 PS - Manual (Page 168)

3 Place the 500-sheet cassette and feeder where you want the LaserWriter 12/640 PS to
be located.
Orient the 500-sheet cassette and feeder so that its paper cassette and the
printer’s multipurpose tray and paper cassette will be on the same side when
the printer is attached.
4 Lift the LaserWriter 12/640 PS, position it directly over the 500-sheet cassette and feeder,
and gently lower the printer until it sits evenly on the cassette base.
Position the printer
over these three posts.
143 Installing Options