He died of smallpox - would they have transported him back to Maughold for burial if living in Michael?

Sorry Sylvia, I have very few 1800s wills, and none from Michael. There was a William bapt 1790 son of John (Juan Dick) & Margaret Cannell, with no further details, but too late for your marriage, and no William in his grandfather John (Dick)'s 1796 will.
It looks as though you need to look at the Michael will.

Sue