Hi Ian,
It would be helpful if you could provide further details as to when Margaret was roughly born, where or why you think she has resided over here? (anyone between 1901 up to the current time, would normally be sought via birth certificates and working your way back.

I could not see any Dacre's in the IOM census's from 1841 to 1901, however, the census's have loads of misspelled words.

Is Margaret associated with anyone else?