Adam & Yves
Director: Peter de Rome (1974) A Hand In Hand Film
An American in Paris falls for a Frenchman; references to Last Tango In Paris (i.e. a stick of butter used as lube), a cameo appearance by producer Jack Deveau, and even a glimpse of reclusive Greta Garbo! My favorite part is probably the fantastic montage of 70's Times Square movie theatre marquees, mostly of "blacksploitation" films, which leads to the all-black orgy in a movie theatre men's room.
Click one of the pics to view the movie trailer (you know that if you view the clip in the browser, you can "right click" and view it FULL SCREEN, right?), or here