Just picked up an Omega D5-XL Super Dichronic today for a steal ... anyways I'm having a lensboard dilemma.
In the picture below, I believe I have the 421-107 slide in mount ... it also came with the other two pieces. I know what the 421-109 is for, and I need it for my 39mm mount lenses. However it will not attach directly to the flat slide in piece ... the middle piece need to be screwed in first. See those black screws? Well if I attach the middle piece to the left piece, the 109 attaches fine with the thumb screws, but then the darn mount won't slide in the enlarger because the black screws protrude too far out the back.
Question is then, are these simply the wrong screws (the two pieces were already attached, I took them apart) or is it meant to be assembled after the slide in flat part is already in the enlarger? Thus allowing the 109 piece to simply come on and off?
Here's another of the back of the board when assembled: