Apple COLOR STYLEWRITER 2400 - Manual (Page 16)

3 Raise the bright blue lever on the carrier.
4 Remove the cover from the plastic tub that contains the ink cartridge.
You can install either the black-only cartridge or the four-color cartridge.
(These instructions show the four-color cartridge being installed, but the
process is the same for either cartridge.)
5 Remove the ink cartridge from the plastic tub, grasping it by its sides.
You may touch the black plastic, but be careful not to touch any other part.
6 Remove the bright orange cap from the cartridge’s print head.
After you snap it off,
dispose of the cap.
Carrier
9 Setting Up Your Printer