I am doing the same thing to my '02 ZX5 right now. First I would buy a Hayes/Chiltons manual for the step by step. But, to get the drum off first take the dust cap off by prying it with a screw driver. Next, you have to get the 4 bolts off the back of the whole assembly which hold down the spindle thing. If you don't take these off you could damage the wheel bearings. You will need extensions, swivel extenstion, and 1/2 inch socket I believe. Next you have to use a 29mm socket and put it on the nut behind the dust cap. You'll need a breaker bar and put a crap load of pressure on that nut. It is torqued to 174 ftlbs. That will get the drum off. Not as easy as most other cars I have worked on. Hope this helps.
Michael Dodge, January 2007