How do I open an iMac G5 17" (early 2006) (intellified)?

Hi all - i tried searching but only found something for the 20" (i realize the instructions may be the same but since I don't know i figured i'd ask). I need to replace a bad internal hard drive. It appears that the "intellified" G5 iMac is not as easy to open as the previous G5 - i read where opening the 20" requires a special tool (a special access card - part 922-7172 - may be required to open the front bezel). My questions: (1) does anyone know if you NEEd this part or is there another way to open it (like maybe using an old credit card?); (2) Assuming you DO need the special card, is there anywhere to get one?; and (3) does anyone know if there are insructions available on the web for opening this Mac and replacing the hard drive?

Thanks in advance

Mark