XRAY - Model racing cars

How exactly do you adjust the front camber?
I assume you add or remove shims to where the pivot balls attach, but do you ever touch the lower arm? Should all the adjustment but with the top arm only?
Also I assume a 1mm shim will give 1 degree of camber change?

Bottom shim is left untouched. On top I don't use shims, there should be more than enough tension in the thread to keep alignment.

I use always 3 degree camber so i don´t need to touch anything. initial setting from kit is 3 degree.