Adjusting B&W Nautilus Mid range drivers

I have a set of N803's in my situation that were received with one driver seriously overtightened somehow. Someone I know that installs B&W's explained to me even though they're factory set that sometimes after you get them into your listening room that the mids need tweaking to balance out the soundstage. Does anyone know what the lb/ft setting B&W recommends is optimum? Where do you get the right tool to set it? Right now I'm running strictly analog using a new Benz Micro Ebony 3H phono cart and it hasn't fully broken in yet and can't tell whether the table needs slight adjustment or my FST drivers still do. I hear huge differences with just minor turns of the screw mostly in how deep and wide the soundstaging gets and the balancing of upper frequencies that seem to be out of balance due to the compression of the mid range driver and it's interaction with the bass drivers and tweeters. Has anyone encountered this issue and what did you do to justify it? Responses are greatly appreciated.