Truss Rod Nut Size?

[HELPnoEMAILconfirmEVER]

I have a 1996 Super Eagle and I can't seem to find the right size tool to adjust the truss rod.  Granted I don't have a specific tool for this so I'm just trying out different sockets and wrenches (US and Metric) but because of clearance I can't get a good grip and I don't want to strip it.  Any guidance would be appreciated.  Heck I'll buy the wrench from Stewmac if I knew what to buy.

Edited 20 hours ago by HELPnoEMAILconfirmEVER