Hello Everyone,

I came across this item mounted on the firewall of a '37 Business coupe. The car had been purchased in California and shipped to Ma.

Ballast for......??

Do a Google search on the information you have on the brass plate. I have no idea, could be something to do with the ignition system.

It might be a ballast resistor for the ignition coil or for the instruments or for some kind of optional equipment . I am restoring a flat base cowl 1 ½ ton truck with a 216 engine at the Museum of Transportation in St Louis MO. Here is the wiring diagram for a 37 Chevy car. http://chevy.oldcarmanualproject.com/electrical/wiring/images/37car.jpg
I have not see anything like the picture you posted.
Good Luck

Should have done that to begin with.......per pics from ebay, it's an ignition coil. Mystery solved !

Here are the specifications for the lamp. I found it at
http://www.donsbulbs.com/cgi-bin/r/b.pl/1116dc~usa.html

category: Incandescent-miniature lamp
volt: 6
amp: 4.17 / 3
watt: 25 / 18
base: BA15d - Double Contact Candelabra Bayonet (or D.C.Bayonet)
glass: RP11
filament: C2V/C2V
fil.res.: 1.44 ohm
i.lumens: 402 / 264
cp: 32 / 21
d.hours: 125 / 200
notes: automobile lamp
clear glass
headlight lamp