Todd...I don't think you need to worry about that difference. In your instructions, I think, just tell you to be sure that each stand/pillar needs to be square to each other and plumb on the N. E. S. & West sides. That 5/8" difference will be compensated for hydraulically as the lift arms touch your car to lift it. On mine I had to use the shims supplied to get them both plumb. I painted the number of shims required for Plumb at or near each hole in the base so I could repeat it later when I haul them out to mount and use again................Bruce.