My guess is that you have a R13 light and a B31 back up light attached to it. Back up lights attached to the R13 were only available for the station wagons. I have the same set-up that I will be using on my 48 Suburban. The station wagon light is the same, the base and rod/rod bracket are different. The Suburban base is round and the rod bracket is longer. The rod is bent differently. I would not pass up this light even if it is for a station wagon, finding a base and components may be hard to find, but not impossible. The R13 and B31 combination is harder to find.
