Good call their an 8EE. I know technically they should have a small chassis as mission mediums start at a 9, but I had the chassis lying around and figured they would work. I wish I knew the differences in length between the small and medium as it would really help. From the picture of your skates, I can't imagine a small chassis has a shorter wheel base at all as there is not much room between your wheels. I would guess, the difference between a small and medium would be where the mounting points are. Does that make sense? FYI, I know that the small Vanguard chassis on the Soldier series skate uses the 80/76mm combination. Good luck! By the way, the skates look great...I think the medium chassis was the right call.