About fifteen years ago when I was building my slabside replica and no one was interested in them I spent half a day at the local Ford dealer going through '60's truck parts books looking at exploded diagrams and found the part in question with the smooth bezel and ordered an NOS one. When it arrived it had one wire and I knew that I needed an ungrounded one, with two wires, so I then found the one shown in these posts that has the lettering on the bezel. After getting an NOS one of those I found that the bezel could be pried off, although it would be messed up. Luckily the plain bezel came off easily, undamaged, and could be pressed on, along with the red plastic lens, the two wire housing . The plain bezel lens is a shiny red ( like the Cobra's) and the two wire is a dull red. So, back in the early '60's either Shelby got one of each of these units and did the same swap that I did or he got Ford to supply the final piece. I have a feeling it was the former since it's about a two minute job and to get a huge organization like Ford to make up a bunch would have been a big deal. So once my experiment of making this lamp succeeded I ordered as many as I could find. I think between me and a friend that helped me figure this all out we got about twenty sets. The last ones got pretty expensive since the supply was going down! I have two left that I may need if I build another car or two, but that's looking doubtful now. I apologize for rambling on but, hey, this is an originality forum and I thought at least one person would be interested. A couple other things that I think are interesting: (1)- Since this light is quite large I decided to make it a "panic light" by adding two small bulbs inside the housing to show low
oil pressure. They are "grain of wheat" bulbs used by model railroaders (my other passion). I wired them in parallel for reliability. So low
oil pressure shows as two spots of light and discharge shows as one. Before I start the car I always check for three lights to make sure the bulbs are good. (2)- I think that Shelby wanted a big light right in the center of the dash to alert a race driver if a fan belt broke or the alternator quit but a tiny light for high beam that wouldn't distract him. So Ford came up with a light from a '40 and a '66 pickup to fill he bill.