I have a 90mm lens (Angulon) for my homemade 4x5 camera and thought a 120mm one would be a nice addition. So I bought the one in the title off Ebay.

It was clearly advertised as being mounted on a Horseman board. But, uninformed as I am, I didn't think this would be a problem.

Well, it is. First of all, the flash connector is on the board, not the (Seiko) shutter. There is a miniature cable coming from the shutter that leads to the connector - I really would not want to mess with it.

Second, I had this bright idea of just removing the lens (with the shutter, of course) from the Horseman board and transferring it to another homemade board of mine. I went as far as removing the rear element, which led to almost removing the front element (almost because it is still connected to the flash socket on the Horseman board).

Next, what fell out was a loose brass ring that was between the front and rear elements. No, I didn't lose it, but I didn't catch how the small opening on the ring was oriented, and this seems critical. I mean, when I put the parts back together, the lever for focusing didn't work anymore, and I think it did before.

So, would anyone have any advice on how to proceed? Should I just forget about the flash sync and do without it (which I wouldn't like)? Does the brass ring have something to do with the focusing lever?