frpp spring questions c/c and height drop

here's my 90 with "C" springs, Koni "reds" and Hotchkis C/C plates. Back in the 90's I had a chance to speak with Kenny Brown and he said "Plates if you lower the car. Lowering knocks your caster all out of whack. The 90's had a revised tie-rod end so offset rack bushings aren't needed, but the front tires need to have the caster repositioned. My tires (245/45-17) are 10 years old and are wearing perfectly even.

FRPP B front 425-530 (1.5 drop) rear 200-300 (.75)
FRPP C front 650 (1.5 drop) rear 200-300 (.75)

As you can tell the C's have a stiffer rate, while the B's are varible.

I'd have to go with whatever these guys say about C/C plates and how far of a drop you can go (on a foxbody) without having them. Although I would recommend them.