Kim, I don't know if you read my previous message yet, but I think I have good news for you. According to the "Biographical Dictionary of the English Catholics" page 469 in the entry for Henry Gillow, "The family was always closely connected with the churches of York and Durham. Robert Gillow, vicar of York Minster, was interred in the cathedral in 1402. His grand-nephew, the Rev. Henry Gillow, was presented to the Rectory of Stockin Pelham in the diocese of London, in 1451, and a younger brother accompanying him to the south, settled in Kent, and was the ancestor of the family recorded in Berry's Pedigrees of that county."
I would say that this must be your ancestors. Now all you need to do is locate a copy of "Berry's Pedigrees" (can't help you there). My Lancashire Gillows also came out of York and were of the same family.