Hi again all,
Having frustrated myself for blundering the Brisfit's wings from the outset, I set them aside and focused on the interior fuselage. Since Irish linen covered most WWI British planes I searched online for images of raw, unbleached, and undoped samples on which i could mix a custom base paint color (recognizing the variables involved):

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After some testing I settled on a hue that felt right, mixed a large volume (for ongoing use), then sprayed both fuselage halves. Next, still relying on the same random 3-view plan I cribbed online, I went about framing the interior by lightly tracing the linen-paint where the various wooden elements should go (measured with calipers). To replicate the woodwork I relied on good ol' Evergreen strips that I pre-sprayed with a wood-looking Tamiya followed by a clear orange coat to simulate varnish. After some progress I noticed the 'lumber' I was using seemed too large compared to the printed plans (first image below). This reminded me of my earlier rib-alignment trouble and how these same plans didn't match Roden's molds. To rectify this I opted to fit the opposing fuselage half with dimensionally smaller lumber then compare the two (second image below). Clearly the smaller framing was truer to scale. "Measure twice, cut once", my old man use to say! In another moment of self-reflection I recognized that, even though this build is just a 'warmup' test bed, my entire approach has been clouded by an element of laziness and impatience. So I stepped away for a bit then went back and ripped out the interior framing I had glued into the first fuselage half. This proved easy because it was all resting atop the same bloody useless non-stick 'primer coat' I had ignorantly applied to the wings!

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One reassuring takeaway from this session: because I no longer trusted my poorly sourced 3-view I motivated myself to consult the Imperial War Museum archive and download the actual side-elevation blueprint of the original F2b (file# Q 68352, if anyone wants a copy). Then for fun I casually overlaid a snapshot of my revised work on the blueprint (third image above). Thankfully they match well enough; however, I really should have taken the time to prep properly from the start before executing anything. In retrospect, I should have skinned the fuselage plastic even thinner, particularly the bottom, and excised entirely the decking for the Lewis gun. Measure twice, cut once!