John Deere Clamshell Headlight AA3075R Refurbish

I was at a tractor show and swap meet yesterday and happened upon a vintage John Deere headlight mounted to a support. It looks like what is on my BN but the headlight assembly will also work on my JD LA, which is missing one headlight. I asked the vendor what he wanted for it and he said, "How about five bucks?" Um, yeah, I'll take that off your hands for $5. People on eBay are asking $30 for rusted out hulks of these things with missing parts, and $50 or more for one in this shape. Someone else is asking $150 for two of these headlamps and supports on eBay.

In this advertisement below, you can see one headlight on the lower front of the grill and a second headlight to the farmer's left. LA tractors got those two headlights. An LI (industrial version) got two front headlights and one back by the operator.

Once I bought the light, I carried it around the tractor show for a while, then dropped it off in the truck. This morning I was showing my wife the new acquisition and it was not until then that I heard it had something loose rattling around inside, so I figured the inner reflector was broken (so much for my good deal). Imagine my relief when I got the thing opened up and found that the rubber gasket had just gotten petrified and the pieces were making the noise. The reflector is actually steel so it can't break.

Here's a shocker, the 6 volt lamp still works! Six volts means the headlight is from the early 1950s or before.

It's a little crusty inside but really not that bad for something that I'm guessing is 75 years old.

Here's everything disassembled. I washed the glass lens and the reflector (which isn't in stellar shape but it will work).

The photo below shows the outer shell and ring painted black.

The gent I bought my LA tractor from had a front headlight mount (casting number L4312T) that is cast bronze. John Deere made them from cast iron so someone has taken it upon themselves to remake some in bronze. New aftermarket cast iron mounts on the internet are north of $150 apiece (!) so I'm glad I have this one.

The headlight bucket's mounting bolt is too short for the brass mounting bracket, so I am making a special nut to fit inside the bore of the bracket. I could just cut the bracket mounting boss shorter but that would forever modify it from a stock length, so I'm going the "special nut" route. And since it's a fairly simple job on the lathe, why not. The photo below shows how short the mounting bolt is compared to the  bracket.

I started with a piece of stainless steel 3/4" hex stock, as it's the only thing I had in a hex shape. I drilled the center out to 27/64", the recommended diameter for a 1/2" tap.

Once the hole was drilled, I set about making the outside contour so it would fit the larger bore of the brass bracket. I then threaded the hole using a 1/2-13 tap. Being stainless steel, the threading was very difficult, so I was able to only go maybe 1/4" in before the tap got too tight to go further. Fortunately it was just far enough so the light was tight in the bracket.

It's not much of a photo but it does show the light mounted to the bracket.