your endlinks should be adjusted to the length required for the desired corner weight - usually, you're aiming for no preload (unless you've run out of reasonable ride height adjustment variations). the only way you're going to know that is if you corner balance on leveled scales, otherwise, it's just guesswork (and most likely wrong).
Level (pre-load being equal) is not that important. I mean, I'd shoot for whatever they looked like STOCK such that there is no potential for the sway bars to impact anything.
