Well, seeing as the Razorback and the Bubbletop kits are really quite radically different from each other in a number of areas, I'd say that an 'N' wouldn't be out of the question. Especially given the mold manipulation that can be done nowadays.
Used to be that if you had a complex multi-part tool (or even a simple one) the join lines were usually very apparent on the finished product; especially if it was badly done, as with AMT's P-40's. But with a company like Tamiya, the results should be much better.
All they would have to do is switch out some stuff on the fuselage in the area near the gear wells. Other than that (and the unique fillet) the external fuselage,
I think, would need no real changes. The cockpit and different engine, yeah, that's a given. They did it with the Razor and the Bubble, so I don't think they'd bat an eyelash here. As far as the prop goes, the bubbletop gives you the four main props used on all variants of the Jug.
The
real change, however, would not be to the fuselage but to the wings. With the 18" plugs at the wing roots and the redesigned outer wing shape, the 'N' had 22 square feet more in the way of wing area than any of the previous variants. And yes, the gear was moved outboard as a result of the insertion of the wing plugs. It was also strengthened.
I'd say that if Tamiya did an 'N', there'd be completely new wings. Again, they did it with the previous two kits, only with those it was the fuselage that changed.
My guess is that Tamiya have developed these kits over a long period of time. When the Hasegagme kits came out, they looked hard to beat. But I think Tamiya took their time with these and tried to make them even more appealing than Hasegagme's. I'd say they not only tried, but they succeeded.
Fade to Black...