I have been away at the TRAIN convention and then some R&R in Essex, Montana. I highly recommend the Izaak Walton Inn. Been going there since 1991 and it is great for family time, cc skiing, railfanning, doing nothing, and building HOn3 EBT hopper cars. Be sure to take Amtrak's Empire Builder for the full experience. End of travelog.
Anyway, when I returned I found that Brendan had made great progress on the boiler and Erich had forged ahead with the frame sections by getting them mostly straightened from the flame cutting process and he has the long one in the planer cutting down the top surface.
The backhead braces are installed, the firebox doublers are installed, the new firebox and crown sheets arrived, and the fillet welding is done on the mudring. Rivet material just arrived and is being tested. The braces will all be removed and the bolted feet will be riveted. Braces will be reinstalled and individually fit and tuned. They will be removed again to allow a crawl space for welding the top of the crown joint, after which the braces will be permanently installed prior to raising the assembled firebox up and in line with the door and flue sheets.

Doublers installed. The side one is the only old one reused.

Firebox halves.

Braces