The springs are rated at 1.5" drop but all springs will settle up to 1" lower than that as time progresses. As far as camber correction goes, SPL Parts
http://www.splparts.com sells S14 CUSCO rear upper control arms that are very high quality pieces that I use on my own vehicle.
I usually try to discourage the Tein S-Techs because their spring rates stink and are more for a agressive look than actual performance. The Eibach Pro Kit, RS-R and the H&R springs are nice quality springs with good spring rates.
If you're only running the KYB GR2 shocks, chances are they will blow out fairly soon with a lowering spring, as they're not meant for that kind of use.
-Dan