KOH week and I still managed to get something done
First arm with its side plates welded up and the head tube tacked in for an alignment test. Had to give it one tweak, test fitted again, good to go, so that got welded up last night. Hoping to get the pieces for the angle gusset from the head tube to the main arm cut and welded up today and get started on arm #2.
Afraid to stick these on the scale when they're done!