Bill, This was discussed in detail in NEHGR, Vol 153 July 1999 (Whole No. 611), p260-277, by Kenneth W. Kirkpatarick. titled 'Isabel/Elizabeth (Bendysshe)(Fytzwilliam) Bradbury wife of William Bradbury, anc. of Capt Thomas Bradbury of Salisbury, Ma.'
You will probably enjoy reading the details.Copies are available thru New Eng. Hist Genealogical Society, BostonThey have a web site.