I have a set of older version Comp Cams Retro Hyd. Roller lifters for a SBC(part#853-16) and ordered some replacement ones of the same Comp Cams part number and they seem to look different than the older ones they have the wheels more exposed,have black stripes and black cutouts on the tops and they do not have the snap rings in the top of the lifters does anyone know if these are a NEWER version of the Comp Cams 853-2 Hyd. RETRO Roller Lifters?THANKS