SOOOO I was starting to paint a brass an O-gauge "South Shore Line" Steeple Cab. I noticed on a painted HO version of the cab there were four 3-sided corner roof lanterns.
My first thought was to buy some cabooses with lanterns and strip those to use. Then I remembered(I'm getting old) that I have a 3D printer. So after looking a a few Caboose lanterns and the HO one, I created a left and right corner lantern with a support bracket to better fix the lantern to the Steeple Cab roof.
The openings on 3 sides will fit small LEDs with a hole at the bottom for the hook up wire. The basic square size is 1/4" square.
Attached is the .STLs
here is how I oriented the prints in the printer.