Don't know if you saw it or not, but I just did a 8.25 and 8.75
Believe me, 6 is too much and you would feel it through the whole car at cruise.
Rusty, I think the "nose up" is when you set the rear end and pinion at zero (like out of the car on stands) then weld the perches on nose up because when on the springs it noses down 6 degrees if I remember correctly.
Mine ended up at 3 all put together and on the ground and is about perfect.
Which means I agree with you in the first sentence of post 9.
