Not really a fix, but a find. I have had a Voigtlander Collinear Series II lens for awhile, having bought it for virtually nothing at a show. It's an ugly bugger but it should still take some nice images. Only problem was that the barrel it came in had had all the leaves of the aperture removed. Wide open was it, and I wanted some other choices.
At another show, I picked up a 1945 Ektar 7 1/2" projection lens on an enlarger board like I've never seen before. It, too, was dirt cheap (get the pattern here?) I didn't know what to do with either of these ugly ducklings when I bought them, but I can seldom pass up a good deal.
Today, I found that the barrel from the Ektar is an exact fit for the cells of the Collinear–same spacing, same thread–and the flange on the funky enlarger board fits a Wolly Sunray 6" projection Petzval I've had for years without a flange. Bingo! Two fixes with one try. I then called it a day and went in to have something in a glass.