Took this from Barnes 4x4
Separation: Link separation affects many of the handling characteristics of a vehicle, making it a crucial aspect of proper 3 link suspension fabrication. For vertical separation at the axle end of your rig, try for at least 25% of your tire size. For example, a 40” tire should have at least 10” of separation. Note: This isn’t always possible and installing links will require compromises.
God... my spelling sux.... +++++++++++++++++++++++OIIIIO+++++++++++++++++++++++++