Compaq Prolinea Family Maintenance & Serice Manual page 126

NOTE: For reference during replacement, note how the LED wires route
through the end of the card guide (Figure 5-43).
7. Remove the LEDs from the card guide by spreading the tabs that secure
the LEDs in place sufficiently for the LED to clear the tab hooks and
pull the LEDs out of the card guide (Figure 5-45).