Flxible combination control panel

This question relates to the 1951 Flxible combination I posted a picture of under the sad pro car thread. There is a small chrome bracket just to the right of the driver under the dash with a knob and two toggle switches on it. There is room for three more toggle switches which are blanked out. I know it's for the emergency warning equipment, but I was wondering if some could fill me in on what the stamped letters under the switch positions stand for? From left to right, BL, RH, F, FD, RD.

Jacob....Interesting question. I've sent a screen grab of the image to McPherson to see if he can identify the meaning of these abbreviations. He says that he'll check some of the Flxible parts books and wiring diagrams to see if he can help. I believe that the large know of the far left would be lighted and for the rear compartment heater - just a guess on my part.

Just a shot in the dark: BL=Beacon Light, RH=Rear Heat, F=Fan, FD=Front Dome, RD=Rear Dome

trying to remember the 66. I'm thinking you hit the RH (rear heater) then the driver could control the fan speed with the knob on the far left. the bl was back ups. you could turn them on for load lights most had a jewel light wired in so you knew what you had on. the front dome and rear dome sound right superior wired them separate. but what would happen is like this car a number of them were left out with the plug in. you wanted a switch for something you just put it there no matter what the label was. after all that was what the label maker was for

The BL for Back up Lights seems to make sense, I thought Beacon Light when I saw it in the car, but there was no zipper in the headliner for mounting the beacon (I couldn't see the roof due to the snow, so I couldn't look for bolt holes, but there was no water damage inside).