So, we know the front suspension moves slightly backward under compression. With the factory positioning of the a-arms, any tire over 30" diameter will rub at the firewall. The a-arms are symmetrical, so swapping right to left won't help. But what about spacing the lower ball joint mount forward an inch and new tubular uppers that did the same? Any ideas? Yes, it would also pull the CV shafts forward, but if you're lowering your diff to match your lift or at least partially, maybe some clearances could be made that also allow moving it forward slightly. If not, then, yes, the CV shafts will have to contend with an additional plane to operate in. Just looking for suggestions.