Mercury 1996 Sable Manual page 226

If your gearshift is on the console, you can use
any of the following positions:
The console-mounted gearshift
The console-mounted gearshift will lock when
you turn the key to the LOCK position. When
the gearshift is in any position except P (Park),
the ignition key cannot be turned to LOCK or
removed from the steering column. TO
REMOVE THE KEY, the gearshift lever must be
in P (Park).
Once the gearshift is secure in the desired
position, release the brake pedal and use the
accelerator as necessary.
R (Reverse)
With the gearshift in the R (Reverse) position,
the vehicle will move backward. You should
always come to a complete stop before shifting
into or out of R (Reverse).
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