I installed a Chassis Engineering rear leaf spring kit last winter in my 1950 Chevy. After an entire summer of driving and a lot of miles the springs have taken a negative arc. I still have to use 3" lowering blocks and it isn't even as low as I want it. The springs have 5 heavy leafs in them, I wanted to pull a leaf and drop some more but when I got under and saw the arc they have I am nervous about doing so. Is it normal for them to do this? Anyone else had this issue? When I ordered the springs they were supposed to be a 3" drop right from the start, never were even close. CE says it is normal for them to settle over time, but how much settling is too much?