69 dart quarter window

You are correct the window takes a double roller. One side fits into the lower window mount and the other to the vertical guide. Iwent thruogh this about 2 months ago . got my replacements from R/T specialties. I bought 2 have an extra one. Also have a complete set left and right side window regulators window mounts ,front and back guides. Regulator work good. I'm selling cheap.