The bottom of a model A body is flat, likewise the top of a model A frame. A 32 frame has a gentle curve to it, and if you set the model a body on top of the frame, it will leave a gap about 1" wide between the top of the frame and the bottom of the body, at the center of the car. Back in the day, many people made up a wooden spacer to fill the gap, and it was sandwiched between the top of the framerail and the underside of the body. a bit crude, but it worked. Then some enterprising rodder came up with the idea of channeling the model a body about 1 1/4", just enough that the gap dissapears. it looks really good, and the only problem that some people have encountered is that the model A body is just a very little bit too narrow at the cowl to slip down over the 32 frame rails. this does not seem to be consistent. Some people report having to "pinch" the framerails a bit in the cowl area to let the body fit down over the frame, while others report that the model A body fit over a stock frame with no problem. This is a matter of doing some tape measure work to see what you are faced with. If you do have to pinch the rails a bit, it is easy enough to do with an oxy acetylene torch and a set of "boat clamps".