I found a Diamond Plate Lava today at a Gooodwill store. The tag said "Needs bulb". I took it home and installed a 40W but it didn't light. I tested the bulb and it was OK. So I tried my old trick; I pulled up on the center contact and Presto!
It's new home will be in my shop with all the other aluminum diamond plate I use for fab. So now I have a Wizard and a Diamond Plate.