I tried general AK discussion, no exact answer,guess try my luck here

I was told that to use upper edge of the slide bar on the rear sight to match the 1,2,3 markings for distance to begin with, and that is how I did from day 1. now the problem is I got a M10 ak 47, came with rpk sights and the manual came with it said to use the middle of the slide bar to match the markings. Now I am totally confused! What do i do?

Also the RPK sights came with M10 is 1-10 type with no "P" or"n" mark, So after I sight in the gun at 100m where do I leave the slide bar for normal use? just leave at bottom? cus that's where my other Aks "P" mark is located?

I really cannot find any thorough info about it, I tried for 3 days search the web, nothing came up. Thanks ahead
here is pic of manual