The only difference that affects anything is the location of the handles and latches. The 1928-29 handle is located further forward and the catch is located on the front edge of the drip channel. As well the rear edge of the drip rail is recessed a little in that area for clearance. The catch for the 1930-31's is located on the rear of the drip channel. To use the earlier lid on your 1930 coupe requires the earlier latch, relocating the catch to the front of the drip channel and cutting some out of the rear drip channel for clearance. I likely have some pictures if I've made this sound confusing. This change was apparently made on the later models so that body damage wouldn't happen if the lid was closed with the handle/latch in the wrong position.
The Jalopy Journal
