Here is the service manual for the Toshiba Personal Computer Satellite L600D/L640D/L645D. Page 4-26 will show you how to remove it. good Luck

UPDATE

Link reinstated

Since you had asked for a guide, I had left the link for the upload. Due to heavy traffic I have to turn of sharing for some of the files. Apparently, a "great many of" my"answers are useless" I figured I might as well tell you what it says in the manual " Removing the display assembly

The following describes the procedure for removing the display assembly

1.Close the display and turn the computer upside down.

2.Remove the battery pack

3.Open RAM Door and remove memory slot cover

4.Remove the screws of the ODD and ODD Bezel.

5.Remove the screws from the bottom side.

5.Disassemble KB Holder and KB screws

6.Remove the screws from the top side and remove the cover.

7.Disconnect the FFC and cables.

8.Disassembly TOP cover assembly

9.Pull out the wireless LAN antenna from the guide with two hands.

10.Pull out the LCD cables from the guide of mother board.

11.Pull out the LCD cables from the guide of LCD panel.

Opening the display to 135degree, keeping display side by hand and remove the hinge screw.

12.Remove the display assembly with two hands holding from the BASE cover assembly."

This way, if you can not get to the manual, at least you know what it says. Hope this helps, good luck.