Odd, that spring should be a bit longer.....another thing to add is a small washer (think a M8 with a small circle) under the inter AFC washer to allow further travel prior to bottoming out but at the cost of coil bind, back off the star wheel to cure that.
One thing I do it try to get the bottom end fuel so faint that it creates turbo lag, then with the pre-boost screw creep up on it 1/2 turn at a time till desired response. A #6 is a good plate with a soft bottom end but you have to raise the foot all the way to the top for it to be right (insert dropping all that crap...screw, nut, washer, in the pump and fishing it out via magnet) might try a 5 instead but I have no experience with it, shape is shorter than a 6 and should be a little more fuel on the bottom.
A zero is a
PITA, hard to tune cause it is all in the AFC, other than that it is on or off!
Jim