Some of the details seen on artist Hosokawa san's cutaway are almost exactly the same as seen on '8D-420' for the Auto Sport January 1971 colour feature and fold-out poster. Note in particular the identical positioning of the wheel brace and jack spindle on top of the spare wheels, which seems unlikely to be replicated on a different day/car.
Clearly Hosokawa san had access to the car, but also ended up having to 'guess' some of the details that he could not see/sketch/photograph, or which he perhaps forgot to note at the time. Myself and a couple of others have long scratched our heads about details like the missing/invisible exhaust manifold, the strange and truncated shape of the transmission, the too-square 100 litre fuel tank and the bizarre shape of the moustache bar, as well as what you have already pointed out.
'985', being Aaltonen's car (their lead and star driver in the rally program) and also placing highest of the Works team cars in the '71 Monte, was an obvious choice to mock up for the magazine's cutaway poster. So, I think the cutaway is a composite of more than one car, with a few mistakes and omissions.
There's a long thread on the Auto Sport (UK) Nostalgia Forum which documents and discusses the work of cutaway artists like Hosokawa san, and there are always many mistakes/omissions/anomalies to be pointed out. I think it is a hugely difficult task to draw one of these things and I'm in awe of the cutaway artists' skill, so I don't want to nitpick too much...