spring question

[porkchop4]

I'm not really sure how to chose springs and I'm kinda wondering where I should start off with on a small 3/8 with medium banking with a 3 link and the spring is on the rear end on the rr and a slider on the lr and should the slider go behind the rearend or in front and its a chevelle clip Hoffman I figured running a 600 on the rf and 650 on the lf didn't know if that's a good starting point

[setup479point2]

If you have a Hoffman just call them . Anytime you have a chassis go back to whoever built it for info . Most of them will bend over backwards to help you.