I've only used them a couple of times and I've usually fitted the 'bone' to the shaft and the socket to the motor....
PS. Welcome aboard the good ship Mayhem!
Thank You, it's nice to be here. Hope I can contribute something someday :)
One might ask "Why won't you just pick one and be done with it", but I'm asking this since I've already, in this very early stage of my hobby, have benefited from adopting commonly chosen approaches, plugs, etc. So much so, that I would even consider it important to follow these conventions, what such there may be.
Searching pictures from the web hasn't really brought conclusive evidence one way or the other. If nothing else, I will most likely go whatever way gets more "votes" here
^Jani