Mark - back in post #1, I showed my two preferred schemes - both are tugs but British wartime schemes. One is RN and the other RAF - standard camo on top and sides and the glorious diagonal black and yellow stripes underneath. Should be no problem seeing which side is up
The stringers were added using 1/8 x 1/16 spruce underneath and on the top spine to help minimise handling damage. The rest are hard balsa same size. As stated, Hutson doesn't notch the formers for the stringers but sheeted bits go on first and notches were cut in the sheeting to fix the stringers on the same former. A lot of work but only one former to support sheet and stringer.....
I had sprayed the interior framing interior green before adding the stringers as these were usually left as wood colour. A 1mm balsa floor was added in the gunner/winch operators area.