Vance Family

My Name is John Vance.  My ancestor John Vance lived in the Shenandoah Valley area.  His father's name was Alexander...Alexander's father was John...and John's father was Andrew from Ireland.  John was born in 1746, served in Revolutionary War in some capacity. I would like info on his participation in the War, his marriage, supposedly to a Nancy Bradley approx 1773 near FT Pitt performed by a Col Crawford (of some fame).  Was John on Washington's staff?  Was he a LT or a SGM.  He must have had some extended level of education...he became a teacher later in life. Any info I receive will be greatly appreciated.  Thanks....John Vance, of the Eastern Missouri Branch.