Scott- Thanks for sharing your drawing of the light setup in the Bennett 256. I came up with a good temporary solution. Used a 3 inch magnet, a lamp socket, a 2 inch lamp nipple, cord and a piece of PVC. 3 inch magnet fit the contour perfect in the top and it will not move. Correct showcase bulb will be about twice this long. Guessing around 10 inches.
ALWAYS LOOKING FOR ANYTHING UNION 76 WOULD LIKE TO FIND A UNION 76 BALL TO DISPLAY NEXT TO MY SHOP.