Taking a break from the panel lines - I've got the fuselage upside down and I'm working from the back to the front - it was time to work on the center bomb section.
I made this out of 3 sections of polystyrene. The section, per the Ziroli design, is close to scale.
I would have had to been more aware before I built this section if I wanted to have the moving doors.
I sketched in where the piping ran and used 1/4" PS tubing. I cut a tube in half so it would fit in the thin area.
This vaguely resembles some reference material that I have. Rivets, a few panel lines and some L channel are still needed.
I'm thinking that tubing etc will be painted zinc chromate. The inset panels will be painted same color as the wheel wells.