Optimus 120-2152 - Manual (Page 10)

4. Insert both of the supplied keys to the slots at the left and
right sides of the stereo. Press the keys downward, and slide the
sleeve off of the stereo.
Note:
The keys are labeled to show their top edges.
5. Insert the sleeve into the dash. Then secure the sleeve to the
dash by bending out the appropriate tabs with a screwdriver. Bend
out all the side tabs.
6. Slide the stereo into the sleeve until it locks into place.
(new illus)
7. If your vehicle has a suitable mounting hole under the dash, use
pliers or a 5/16-inch box-end wrench to attach the short end of
the supplied mounting bolt to the back of the stereo.
8. Reconnect the wire harness and the antenna.
9. Reconnect the cable to the vehicle battery's negative (-)
terminal.
10. If you are securing the stereo to an existing mounting hole under
the dash, push the supplied rubber mounting grommet onto the
mounting bolt, then push the mounting bolt (covered by the
mounting grommet) through the existing mounting hole then slide it
to the left or right to secure it.
Otherwise, you can use one of the supplied bolts (with attached
washer) to attach one end of the supplied metal strap to the
mounting hole on the back of the stereo. If necessary, bend the
metal strap to fit your vehicle's mounting area. Then use either
the supplied sheet metal screws or the other bolt (with attached
washer) to attach the other end of the strap to a solid metal part
of the vehicle under the dashboard. This strap also helps ensure
proper electrical grounding of the stereo.
REMOVING THE STEREO FROM THE DASH
If you ever want to remove the stereo from the dash, follow these steps.
1. Disconnect the cable from the vehicle battery's negative (-)