Based on the pic, it looks like the clearance between the chain and dropout is about what you would expect for a road bike with 9 or 10 speed cassettes. How the chainstay & seatstay are connected to the dropout may be different for newer frames but nothing you can do to this frame to change that.
As for the thread about respacing a hub for 126mm, that thread entails moving the freehub body CLOSER to the dropout. Don't think that is what you're trying to achieve.