Pull two mains at once at the head, never at the handle. Same with the Head IGS.
The problem there will be with the crosses which need to be pulled and clamped before inserting in the inner grommet.
Unlike the O-Port frames, there is no tool to help with this.
IDK if 50/50 will work on these. You may just have to use the old 'hip-brake'.
Neos 1000, Eagnas Combo 810