Sykikchimp- you should have nothing to worry about, the install is very straightforward (despite which I still managed to take a couple of hours). I would set aside a good 2 hours to make sure you have everything on right, and to make adjustments to ride height, spring compression, front camber and dampening adjustments.
Re: height- I would leave it at the heightthat they came with for the time being... in fact you may consider RAISING it a little bit, as they (or mine, at least) are low enough for me to scrape my cat on large speed bumps.
A good starting point is to just have the 4 set at the same height, and work from there.
Also, make sure your spring perches are tight, and that there is a little bit of pressure on the spring; you don't want your springs becoming completely unloaded and moving around when you lift a wheel going over rumble strips (or just a big fat pothole that you didn't see).
Let me know which way you install your rears (you'll see what I mean when you get to it), I'm curious as to why you (will have) installed it one way over the other. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt='
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