Oops, not Vol. 5 and Vol. 6._Pennslyvania Archives_Series V, vol. 4:429ff and Series VI, vol. 2:399ff.
There are also fragmentary lists for Westmoreland County Militia in Series III, Vol. 23, around page 225 and around page 320, which include what seem to have been companies on this expedition.Specific information on it is not easy to find.