Texas Instruments TravelMate 4000M User Reference Manual page 217

Options
3.
4.
5.
12-16 Portable CD-ROM Docking System
Remove the battery by pressing the release button and
sliding the battery out.
Remove the four screws beside the recessed area in the
battery compartment of the Portable CD-ROM Docking
System.
Open the SCSI drive kit. This should include a SCSI
connector, metal bracket, plastic cover, screws, and
installation instructions.
Battery release
Remove screws