I replaced the cord on the power supply for a Graflarger back which I have adapted to fit my B&J. Now if on Worldwide Pinhole day I use up some old 4x5 film laying around here, I may be able to enlarge it! This thing was salvaged out of a junk pile circa 1960 and I've never used it -- but it lights!

I drilled the metal case and added a ground lug and used three conductor cord, so if it runs amok, I don't light up.