I do pretty similar - Meg's Ult Wax (the newer version of NXT) & D156 / UQW after the wash. As Mike P points out, gentle wash. I foam gun it to get it loosened, as well. LOTS of soapy water on a MF mitt, 2 bucket wash, etc.
My car is overdue for a wax but you couldn't tell - it's SO slick...