I have one of these and I'll just say, it's a super sturdy body which is great for experimenting with certain heavier lenses. I use various big process lenses on it. I also use the rb67 and rz lenses on it (hand shuttered). It's an excellent LF body for macro, very sturdy.
Yep. What I did was use a rear lens cap to affix the rb lens to a lensboard. Really easy. And the rb / rz lenses are great fun for closeup 4x5 and 5x7, especially the fast rz 110/2.8.
Erie's gizmo is nice if you need the shutter speeds. Since I am mostly doing close-ups and macro with longish exposures, I just hand shutter. All I use is the lens itself, no other rb parts. Then it's just an issue of getting the lens affixed to the lensboard.