How can you tell if a brass headlamp or side lamp is a reproduction? I've heard that one way to tell is that the glass on the original side lamp is thick and beveled, whereas the repops are flat. Is that the only way to tell?
On the mounts the originals are steel with a thin brass sheet around them.
The repops are solid cast brass.
I'm not sure of the exact differences, but I posted a number of pictures of E&J repop lamps in the classifieds that may help you. They are the lamps that Chaffin's sells. You can see the glass is beveled on both the square and round lenses of the side lamps, and all of the lenses in the tail light are domed. The pictures may be good for reference.
I find that after 100 years if the lamp is perfect beware all those new rads stand out. You will also find that when polished the repro does not shine the same our brass when polished shines almost white a friends car with repro brass when parked beside us is more gold. He is trying to make it the same as ours maybe it just needs 100 years of polish. I see it in pictures with a new rad and original lamps they don't match. Maybe I'm just old and my eyes are bad. Cheers Colin
E+J 666 head lamps the mounts are different and the vent at the back of the hood is missing between the 2 holes This picture is the real deal