The Metra kit should work with ANY 2 din HU so just pick whichever HU you like and can afford. Detachable face HU's will generally cost more, but if you gotta have it... $$$
As far as factory alarm compatability? Not a clue. The factory Delco radios with the Theftlock function have their own security system built into the HU itself AFAIK
. It needs the unlock code if you disconnect it or pull power and have to reinstall it as I understand it. I don't believe it should affect the factory car alarm when you just swap out the factory HU for an aftermarket one. I'll know for sure after I install mine.
If you buy from Crutchfield (who usually tosses in the install kits free), let them know that you want that particular install kit. Crutchfield will probably try to tell you that it won't fit because their computer tells them (incorrectly) that a 2 din HU won't fit a F body. If so, tell them that it's for a custom modded install and see if they'll work with you on it. Can't say for sure as I've never dealt with Crutchfield personally.
I researched it quite a bit, and from everything I've read, that's the one (Metra 95-3302) that is mentioned as being most appropriate for the '97-'02 Camaro (and many others). The second post in this thread -> http://www.camaroz28.com/forums/showthread.php?t=800820
has a few very helpful links in it. You'll just need to nip a bit off one of the lower tabs on the install kit side brackets to make it fit.
BTW: I got my harness adapter wired to the new radio plug already. I just needed to get my electrical connector kit before I could finish it. Since it was in my storage unit about 1.5 hours away from me, I had to wait till I had some free time and better weather to be able to go out there and get it. I went and picked it up today, as well as my Dremel kit I'll need to mod the bezel, so I'll finally be able to make some progress on the install again.