I got mine installed about a month ago. I find they do react noticably quicker than the stock steel springs.
I used spring hangers from DrDiff, had to weld up the hole and move it forward 1/2" as the Hyperco front segment is 20 1/2" and added a gusset plate to the top. I got the 175lb rate , wish I had got the 200lb rate .

I had to machine up some spacers so it fit in the hanger .


Also machined a spacer for the location pin