I am a descendent of Georg Heinrich Funfrock (Fivecoate), a son of Michael Funfrock Sr., born in Schwabweiler, Alsace. Our Michael also came to American in 1750 aboard the ship Sandwich, presumably along with his wife Barbara and 5 sons, including Georg Heinrich. There was another son (8 sons altogether) - Johann Georg, born 1748. The family tree just from this group is confusing because the first name of almost every son was Johann. Anyway, we show another son - Andrew Peter, born 1760, who married an Anna Margaret. Could it be we are related?
As far as the name change goes, I don't have anything definitive to share, but I do have a will from a descendent of this group approx. 1850 bequeathing his farm to his sons - and the name is spelled three different ways within the same document!