Apple Macintosh PowerBook 1400 - Manual (Page 172)

4 Use a small flat-blade screwdriver to remove the expansion port cover.
The cover is held firmly in place by small tabs. You may need to pry it off by
placing the screwdriver in the small indentation at the center of the cover’s
right edge.
Be sure to save the cover so that you can replace it should you remove the
expansion slot card later.
Expansion
port cover
Small flat-blade
screwdriver
172 Appendix C