Thrift store score
 

Picked this up today at my local thrift. Hoping I can use it and get it working. Not sure what the hole in the back is about. Will try to find a plug to fill it. It's a Unity brand and looks fairly old. http://i196.photobucket.com/albums/a...icture1159.jpg
http://i196.photobucket.com/albums/a...icture1161.jpg
http://i196.photobucket.com/albums/a...icture1162.jpg

Re: Thrift store score
 

Your spotlight appears to be a standard 5” Unity model. Judging by the wire, ivory grip, and wedge pin holding the handle housing to the shaft it was probably manufactured somewhere between the 1940’s and the 1950’s. The outside mounting bracket might be a universal model 31L which will work on 60-63 trucks. There should be a model number identification on the back side of the casting. The following threads may be helpful in getting it working: or mounting it on a truck:

http://67-72chevytrucks.com/vboard/s...d.php?t=403869

http://67-72chevytrucks.com/vboard/s...d.php?t=401449

The hole in the back is a puzzler. At first I thought it might be for an accessory spotlight mirror, but I’ve never seen one mounted in the center. They usually have an offset mounting bracket like this one currently listed on Ebay:

http://img40.imageshack.us/img40/567...ightmirror.jpg

Good luck with it, they can be a fun accessory.