That back-up light was offered in early 1947 and was soon replaced by a different style that looked like the parking light and mounted under the tail light either singularly or in pairs. This light mounted on the lower left deck lid after drilling a large hole in it. You need to want either of these back-up lights badly as you have to make holes in the car to install them and they are not very frequently seen. 1949 and later back-up lights were mounted on the rear bumpers of the cars. It looks to have all of the major parts and it originally came with an instruction sheet.