Aside from the alternate Gundam head, it also has about 3mm extensions to the forearms, something inspired by the slim look of the GMs in the Light novel Blazing Shadow.
Here's some additional articulation added to the ankles, which I adapted from a White Dingo build I saw in an issue of Hobby Japan
And here's a mod to the beam rifle the custom unit will use, to make it easier to paint (and less of it to mask off.)
I'm thinking of making the unit's main color green with some dark gray for the limbs and maybe desert yellow for the vents and other panels. something similar to the GM Striker color scheme.
Anyway the deadline for this build is still far off (June, Toycon season) so I'm just taking my time with the modifications.
Oh and I finished this during the weekend,
as usual I'm going to be lazy and post gallery pictures really late. I haven't even done a decent set for my other finished planes. Just not feeling up for documentation for some reason.