Removing Bottom Cover of PowerBook G4 15 inch Model A1138 1.67ghz

Hey all I am trying to replace my hd with a bigger one, in my powerbook, now I have been looking all over for instructions on how to do this (remove the bottom) but all I can find is for older powerbooks and they don't work when I start reading through the instructions. Basically I remove all the screws on the bottom side of the laptop and get to where it is loose, now I am not removing the two top screws (one located next to the powerbutton, the second directly across) But I don't have a screw driver to remove these, so i am not possitive if i do. If i do need this does anyone know which screw driver exactly it is i need so i can go buy it. If not what do I do next because I dont want to pry to hard and break anything. Thanks.

Assuming you have Model #: M9969LL/A (PowerBook G4 15-inch Double-Layer SD), you can get a take-apart guide here: link