Piston ring id question

Hello guys,
I finally stuffed my pistons in the 540 yesterday. It went really well. After I installed about 3 pistons, I realized I was installing the top ring upside down, it had a dot on em and this is supposed to be installed facing up, so I had to redo 3 of them.
I lost the original instructions which came with the rings. They are the total seal standard plasmamoly ductile iron top rings with a cast iron second ring. Dumb question, how can u differentiate between the 2 rings, since they are the same size? One of the rings is shiny on the face with a smaller dot, the other one is black with a larger dot. I assummed the black one is the ductile iron top ring. Hope I'm right.
PS if u ever want to install pistons, get a taper ring compressor, it is awesome!!
Thanks Ed

top ring shinny color not as dark most of the time if moly sometimes you can see the moly on the face. dot up if a bevel faces up 2 rings black bevel at bottom dot to top .top ring no marks no bevel then its a barrel face ring and can run any way there is no top or bottom .any marks allways face up on rings