Also. You say about a slotted inner joint being negative. Dependant on the cars body obviously our beam could be better or worse than 6degree.

The 6degree is made bang on the centre of the slot if I am not mistaken. And with it being toe adjustable on that slow a tiny tiny amount makes a big difference as it's across the arm. So if your being anal about it it could be a 5.8-6.2 for example