Seeing that your L/R speakers are only about 7 feet apart or less, you should need very little toe in, since you are sitting 10 feet back from them. Are you able to get a laser pen or some other laser pointing device so you can create a target for the 2 speakers to converge on? I don't know what type of display you have in between the speakers, but if it is a televsion of some sort, how far forward do the L/R speakers project in front of the screen? Are they equal with it, etc? Of course, there's always checking to make sure your speakers were not connected out of phase by accident.