Here is what I think I have. It looks like 47-49 had the high beam lite at the top of the speedo. 50-53 had them at the bottom. I probably have a 50 speedo housing with a 47-49 cluster. Some one probably used a 47-49 cluster as a donor into the 1950 housing. They put a 0-90 sticker on the old 0-80 face plate. I can drill a hole to line up with the bottom lite tub but I wonder if the speedo will register the right speed if it is a 80 mph cluster with a 90mph stiker?
It will register no worse than the correct setup. These old speedometers are not going to be precision instruments.
Carl