Well done Gilmer and bim you'll both do OK in the Smoke
I spent my teenage years learning to suppress my cockney accent as although picaresque it is not the best thing for getting a decent job so now I sound more like Jamie Oliver I guess (a mockney)
These alternate or slanguages are never very politically correct, the cockney word for an American is (and please accept my apologies at this point) "septic" - septic tank = yank which I believe started in WW2 when British men resented Americans for their money and smart uniforms and access to toiletries and hosiery, all of which British women rather liked