I'm looking @ putting 572.5cf's (5x7's for the rear) and 60.5cs' (component 6.5 for the front) in to replace my stock stereo in my sport package (no Bose). I was just wondering if I can just pop them in w/o any problems (impedence, etc)...

Should be no problem regarding the impedance - but why 5x7 in the back? The stock speakers are 6x9.
Also, if you want to put 6.5 component speakers in the front, you will likely need some sort of a mounting adapter because the stock speakers are 6x8 size (as far as I know).
Actually, this information is based on posts of other people on the forum, since I have not replaced any of my speakers yet. However, if someone can chime in with relevant info, I'd be very interested too, since speaker replacement will be the next thing I plan on doing as well.

There was a thread with some instructions by KKMmaniac about how to take off the door panels.

I brought my car in to a car stereo shop and they're the ones that recommended those speaker sizes (they were focal's and jl's in their $2500 estimate). I could probably go to the 6x9's. I'm having another shop do the install, so I'm sure they'll get the speakers in.