Yes I'm still pegging along. Not much further backward (so to speak) with this pair (my 5 times great grand parents). "All (I) know" is a tall order!
I have a contemporaneous Joseph Vaughan who married Elizabeth Jones in Lea/Newland Gloucester 24th July 1724 (also my 5 x GGP), and given the apparent rarity of Joseph Vaughan individuals I have conjectured that they are cousins sharing an (unlocated as yet) grandfather Joseph.
I identify my 2 known Josephs as of Rockfield and of MelinGriffith (the tin plate works).
Joseph and Elizabeth spawned my 4 x GGF Thomas Vaughan (1731-1822) who left biographical notes.
Ann Price (1699, Rockfield-1782, Woodside) was the daughter of Thomas and Bridget, her will may be the one in National Library of Wales (1783, widow, Rockfield)
Joseph and Ann had a daughter Ann (1731-1791, Pentyrch) who married (8-5-1755, Rockfield) Thomas (1731-1822, Whitehouse), the son of Joseph and Elizabeth. Their daughter Ann married Howell Yorath (my 3 x GGP)
Perhaps if you could be a bit more specific about where our ancestors might coincide, I will dig out any pertinent stuff from my files.
peter