$&¥£#% Steering gear NUT stripped!

I was just out looking at mine. That welded nut does not seem accessible as you say (from what I can tell).

You could just drill it and tap it for the next higher size provided the new bolt head still seats properly on the steering gear and bolt thread still clears the gearbox thru hole.

Alternately, I found this cool thread repair interesting but haven't used it. You'd have to remove the steering gearbox (likely) and drill but could maintain the same bolt size:

http://www.timesert.com/index.html

Check out the installation video, it looks like a quick fix.