You can put a 2k5 frame on it, but you'd need a 2k5 (alias style) board, membrane pad, alias length eyes, battery harness, and all that jazz. It is indeed a 2k2 intimidator. I honestly wouldn't put much into it, I'd keep it like it is.
I think the g6r trade is worth it for a nexus though. I wouldn't think twice about it actually.