What's the depth of the lower chassis, is there enough clearance for the input caps when unmeshed?
Plenty of clearance. I have made that mistake just once before...eons ago. I had a load cap below the chassis, and unmeshed the damned thing didn't have enough clearance to bottom cover.
These cabinets were made by ICA manufacturing. He makes various sizes..and I think this one has aprx 4" below the chassis. I will check on Thursday. The cabinet for the B+ supply has already arrived..and is a lot bigger, like ( I think 22" x 22" x 19" tall). The bottom of that pwr supply cab gets re-enforced from below..and 4 x casters installed.
I built my own chassis from scratch, and used 5" below the chassis, so plenty of clearance for the pair of broadcast variables etc.
BTW, I just posted part 14 a while ago. Part 15 comes out thursday, or possibly friday.