I have one Gray & Davis #15 tail light and one left side Gray & Davis #104 side lamp to sell. These are nickel plated, a Cadillac option in 1911.  Other vehicles also used these lamps.

The tail lamp is in excellent condition, the side lamp also very good, with one small dent right on the top. All glass is good. $500 USD + shipping for the pair. Will sell separately if necessary.

Picture available here:  https://russellcars.ca/lamps.jpg