So I got bored... I was blanking out on what to do with an extra back I had for an RB67, and I was musing on a pinhole, so; voila! I removed the RB adapter, and added a spacer that I cobbled from a plastic display box that I had. Serendipitously, they fit very well. A good deal of felt, some wood to create light labyrinths, black caulk to fill the gaps, and a nifty handle from Home Depot, and I have myself a pack film pinhole! So far, I'm quite happy wi the results, and the aperture seems to be around f256 or so. Not super small, but I like it! I'll post some shots in a bit. Great afternoon project. And I'm really proud of the box too! Ps. Brain fart... No idea why they are sideways. I can make this yet the tech eludes me... Gah!