DO not under any circumstances attempt to modify your charming American accents. Britishers enjoy the challenge of directing you, e.g. "Tooting Common" will take you on a circulambulatory tour of hitherto unexplored regions of the country - which is far more educational than a boring old exhibition of Tutankhamun.Similarly, the Arrivals desk at Gatwick will cheerfully spend hours checking maps, calling colleagues and rival companies to get you to "Sehv-enh-noh-axe". This is far more congenial than a boring bus trip to "Seven Oaks" in Kent.
And for your return trip via Jamaica: take the TRAIN at Gatwick if you want to go to KINGSTON. Connex SouthEast to Kingston, Surrey will take you on a comfortable, clean and quick journey with only one change at East Croydon.