A pic of the forend system. Even though nothing is soldered, the system provides a good lock-up. Most lever releases I've seen pics of have a metal nose cap which I believe houses a spring pin or ball. Along with a detent in the release arm it provides a positive lock. The ease of the lever is quite surprising, I have 3 shotguns with push-button releases which are fairly hard to operate. I'm guessing the relative speed of disassembly made the lever system desirable with doubles. I saw a pic in a book I have showing 6 doubles in a rack, at least 4 had the lever.
Another view of the right side of the monoblock getting ground down. I grind, then use a 50 grit belt sander, then a disc sander. Then, the files. After the barrels are done, I'll go back to the forend and remake with more care.