I just popped my sister's xt345 open last night. You need to go through the keyboard. First, remove all the case screws from the bottom. You don't need to take the screws out that hold the ram cover. Next, remove the screws around the sides of the unit. be sure to take out the screws around the lcd hinges. Don't lose any screws! Open the lcd screen as far as you can and put something under it to support it. You will need to disconnect the screen. To do this, pry up with a small flat headed screwdriver on the plastic part that goes around the keyboard near the upper right hand side of the keyboard. You should be able to remove this piece and the lcd. The lcd is connected to the unit and will need to be disconnected. Don't force the connection loose. After removing the lcd, you should be able to start pulling other pieces apart. There are several screws to remove the keyboard and a hidden screw under a foam-type insert to get the touchpad out. The actual cd unit can be removed only after the keyboard is removed as there is one screw towards the back of the cd unit and it is connected in the back as well. While facing the cd drawer with the screw removed, gently slide the cd unit towards you. It should release easily.
The whole process takes some time and a bit of frustration, but once you get it open, you should be able to do what you need to know. I'm no expert, but I can try to give additional guidelines if you need. Good Luck!
I'm currently in the process of replacing the cooling fan /heat sync for my HP Pavilion xt345 (about 6yrs old). I'm having some difficulty removing the case. Does anyone know the trick to getting the case opened? It looks like the DVD-ROM needs to be removed but I can't see how to get it out. If not, does anyone know of a online reference to assist me in this process? Thanks in advance for your time!