> Tomorrow can you please post a screenshot showing some of the faces that are in the wrong direction? I'd like to closely inspect those areas to see if I can figure out what might be happening there.

Here we go. I've added comments directly in the images (I'm a bit lazy) ;-)

(Edit : forgot to mention that between image 7 and 8 polys were "manually" flipped. Can be quite tedious in Modo with an object made out of multiple parts which is why I prefer to merge the vertices)

Cya

Schbeurd