cgallant wrote:for that nut, you should be able to use an open ended wrench. Shouldn't have that much torque on it that you can't get it off...

I have to say that this is a dangerous game to play. Thos nuts can be pretty tight if a cowboy's been in there before you.

Just grind yourself a dedicated 12mm ring spanner (wrench). That's what I use.

As for a crowfoot fitting for tightening up, good advice. Never got around to it myself, so welded a 12mm nut onto the (ground down to fit) 12mm spanner. Perfect.