4-Wheel alignment requires the rears to be set first so that the Thrust Angle is correct. Is there a DIY method for doing it? The fronts are then set against the proper rear setting.
Having had mine aligned at the local tyre depot, I found the rears could then be tuned to the sweet spot using a Gunson Trakrite gauge.
https://www.youtube.com/watch?v=X0ytDJ0mJoQ
TC