There are actually no set rules regarding near field monitor placements. Some engineers prefer their NS10s to be by their sides; some are standing up. Depends on your preference. But if you put them by the side, make sure the woofers are inside and the tweeters outside for better stereo spread. In our case, our mixers being huge, the equilateral distance of our NS10s vs a vis the mix position is about 6 to 8 ft, positioned in such as way that the high frequency drivers' convergent points are about 1 to 2 feet away from the back of the head of the mix engineer.
BTW, originally, the tweeters of the NS10Ms are to be covered with tissue paper as they are suppose to be very bright. The NS10 Pros though were suppose to have been compensated already that the tissue matter is removed completely. Bob Clearmountain used this practice in his monitoring.
FWIW