if they are really close dont cut em, just score and fold. some of those folds on that right side piece i only cut half of the actual fold, then just scored the rest.
for the mohawk i hot glued it on around the edge of the base, then cut 3 holes in the underside (think ladder) through both layers so i could get some rondo in there.
with scaling i took 2 bookends and then put my head in between, ear to ear, measured the distance then added 5mm. then just...
ill see about getting some pics up. once you finish the jaw you will see how it attaches, i glued it to the main part of the helmet tho. i did not use the eyepiece, other than the center bridge over the nose.
you can explode the view under the 3d menu... view setup.
I recently completed the helmet so I know what area you're talking about. the mountain/valley fold area you are on is more of an error at that center area. If you zoom in close on the 2D menus of that piece, you will see a very small fold. Ignore that mountain fold and just attatch the edge...
Sounds like you're trying to take some shortcuts and its not working out. I've been tempted myself but I hold back and take my time. I'm working on my first attempt at war machine armor, trying to make it somewhat decent. I'd say hot glue the tabs together, coat the outside with resin, then...