>>9152019>>9152108I don't think you realize how hard it is to fit an entire new frame into another kit(unless you're only thinking about the joints which wouldn't be a bad idea), you're much better off modifying the current systems in some ways.
if you're thinking about shoulder and arm articulation you could just replace it with the bog standard flip out joint most newer HGs have and separate the shoulders to be attached onto your new shoulder joint(s) instead of the upper arm.
I think you're much better off just buying joints instead of an entire frame.
