IBM PCjr Hardware Maintenance And Service page 324

Top Cover Replacement 852
1. Connect CNK (control panel cable).
2. Set the rear of the top cover onto the bottom cover
with the three rear tabs under their latches.
3. Pivot the the top cover down until it closes securely.
4. Tilt the printer up, and install the cover mounting
screw.
5. Connect the power cord to the printer.
Rear Tabs
4-850-4 Compact Printer