I've been away from this project for too long due to a number of "honey-do" jobs and a fishing trip to Guatemala. I got back at it this past week and got a bit accomplished. I took the barrels to the micro-welder and had him fill in the seam in the rear face between the barrels and the mono-block. After some careful filing, smoking-in. and stoning, the barrels are back on the face and there is no longer any seam visible. I then finished cutting the chambers that last few thou and have good tight headspace.Here are two photos of that work:

I also spent quite a few hours smoking-in and filing the top rib until it fits perfectly on the barrels. I wish I had a dollar for every time that I screwed on and then un-screwed that rib this week past! Here are two photos of that work:

I'm now ready to pre-tin the top and bottom ribs and the barrels with Hi-Force solder and then do final assembly, hopefully by the end of this coming week. More photos in a few days.