Augustowski Family History

Hi,
My great-great grandparents, Marianna and Jozef Augustowski came to England from Poland in 1858 with three children, Kazimierz, Wincenty and William Francis. From Polish records we have found Jozef was a jorneyman tailor working in Warsaw. We have also found Jozef and Marianna's marriage certificate at the Parish of St Cross, Warsaw. Both were converted Jews. They settled in Whitechapel, London and have changed their surname many times on various census returns. The last trace I have of them is on the 1901 census. We think that the decendants are using the surnames Williams and Angus and probably aren't aware of the original surname.
If anyone can help I'd be extremely grateful!
For further information please see my very basic website: augustowski.com
Many thanks