At a train show a guy sold me a scale 0-gauge Atlas boxcar with beautiful detail, paint and lettering. It was 2-rail. But very cheap. So I thought I'd try a 3-rail upgrade on this car. Is there an inexpensive way to do this? can I pull some old 3-rail truck/coupler combinations out of the junk box and use those? Or am I better off keeping the 2-rail trucks on the car and using a body-mounted coupler? Maybe one of those that has a big box, long arm and springs to center? All advice welcome.