OK So I got the whole "Z" height thing, but I'm crawling under there, and don't have a good eye for the lines they use. Does someone have a baseline measurement for say, middle of the fender lip, for the stock height of '03 4x4 Ext.? My bumpstops are just touching the lower arm and I'm thinking this must be too low. Also- I've got 275/70-16s @ 31", so I figure to add 1/2" for those.