not a fix but, i made a simple thick card stock lens board for my durst enlarger as i couldnt find the correct lensboard for sale that fit the non standard 150mm lens i put on. two pieces of thick cardstock glued together, I cut a beveled edge by hand so it could lock into the retaining clips and screw like the oem lapala board. blackened it all up with sharpie, and sealed the cardstock edges with clear nail polish so they wouldnt fray with mounting and unmounting. was leaking a bit of light so i put some foam strips on the edge all the way around as well.
next time ill make one out of wood or plastic, but I didnt have any around in the right thickness this go.