I'm pretty sure these are not stock, but hoping someone can identify it.
These are on the tail of my 66 F250 Camper Special as backup lights. On the bottom edge of the glass is "I.G.C." and "5935955".

 

Not 'stock' as backup lights weren't available until 1967, but what this lens/bezel is from, I don't know.

7 digit part numbers were used by GM, Studebaker, Packard and others. It's not from a Packard, doesn't appear to be from a Studebaker either.

Look at the bezel, see if there's any numbers on it.

 

Looks like it might be from a late '40s / early '50s Cadillac parking lamp. Searched on ebay with "IGC 5935955 Lens" and there are some of the lenses for sale that look just like it. Nobody seems to have the bezel and mounting plate though.


I may need to find me another option to replace these.

 

It's not a parking lamp for any 1948/50's Cadillac, it might be a backup lamp from a 1948/50.