>>23489392
To use another combiner as an example, Moderoid God Mars has you build all 6 components separately, yet in order to get the on-screen look for both the individual robots and the combined Godmars, you basically have to dismantle the arm/leg mechs by removing pretty much everything except their torso, then slapping on an additional part below that to attach pretty much the entire lower leg. This is everything you're left over with.

Fun fact, I used the blue leg pieces from Sphinx as the backpack parts for the Earthshaker Hound last groupbuild. Yeah this puts me in the scenario that I'll never be able to properly display the six together, but I bought the thing for Godmars, not Gaia, Sphinx. Uranus, Titan, Ra, and Shin. However it's completely understandable to want to display Hyoryu and Enryu on their own instead of ChoRyujin since they're actual characters instead of mindless combiner drone pieces.

>>23489399
A thousand times yes. If not for adhesion then to just ensure you get proper color coverage.