i have researched this for over a week and only info i could find were for the upper ball joints on 4wd. i know some guys used washers as spacers when they did the bj flip on the lowers, but wouldnt solid spacers work on the lowers too? my way of thinking is if the spacers are strong enough to take a beating of off roading, why wouldnt they be strong enough for a truck driving low-n-slow? using lower bj spacer would locate the spindle exactly where drop arms would locate it, so i dont see a huge issue with alignment and putting upper bj in a "bind".

 

yup, that's how it works. solid spacer is about 50x better than a stack of washers. Just gotta find/make it.