Alignment shop wants to start with front sway bar only??

I only did the front on mine, to eliminate the toe changes and resulting bump steer that occurs as the Twin I-beams go through their range of travel. Worked out exactly as I wanted. An E450 already has a substantial rear sway bar, much thicker than the wimpy OEM front. Also the late model E-Series chassis (08 and up) have heim-jointed front sway bar end links. No rubber.