I've ran accros a book that may help: Historical Collections Relating to Gwynedd: A Township of Montgomery County, Pennsylvania, Settled 1698 by Welsh Immigrants" by Howard M. Jenkins reprint 2009
Squire Boone and Sarah Morgan want to marry and make that obvious to the Quaker community, a declaration of intent, on pg 116
As for performing marriges; that I don't know.
Ancestry.com. Historical collections relating to Gwynedd : a township of Montgomery County, Pennsylvania, settled, 1698, by immigrants from W [database on-line]. Provo, UT: The Generations Network, Inc., 2005. Original data: Jenkins, Howard Malcolm,. Historical collections relating to Gwynedd : a township of Montgomery County, Pennsylvania, settled, 1698, by immigrants from Wales, with some data referring to the adjoining township of Montgomery, also settled by Welsh. Philadelphia: Jenkins, 1897.