Ron Sutton has a few really informative discussions on ProTouring.com about front suspension setup. His thoughts are primarily from years and years of setting up everything from a 1/4 midget to NASCAR to LeMans. Keeping the tires as flat as possible with the tarmac to achieve maximum grip possible. He has figured out that caster needs to be at least one degree more positive than the KPI/SAI measurement of the spindle you're using as a general base. I have roughly measured my 73+ A body spindles at 7.5*.