"Bozart" is likely a variation of Bozarth, especially since it occured soooo early on, when spelling was not important, and not standard; and when accents were "normal", and scribes didn't speak French, and were not necessarily English themselves. Mary is probably a granddaughter of one of Simon's sons. (probably Thomas', maybe John's daughter).I don't have it, but there is quite a bit known about John's line.
Simon had a daughter named Mary, but she married Richard Longman and I think there is quite a bit of history on her.
Please contact Gayle Mark at firstname.lastname@example.org.Gayle is the editor of this important family publication, and may have good leads for you.
I, personally, am not familiar with the names you present but I encourage you to post a message on this site, ie BOZART - Mary 1750/60's and then the rest of the names.
As you probably know, it is not at all uncommon for women to die quite young ie childbirth and for men to quickly remarry.Socially it was "kinda" obligated - as women were completely unable to support themselves.
Good luck searching.Let me know if you find her - I'm interested.