Header Nut Orientation?
 

May be a minor point...but I can find no reference to the proper orientation of exhaust header nuts. These nuts have a small split near one end - and I would assume that this would face inwards to act as a locking mechanism - except I noticed that these nuts were in the opposite orientation when I recently pulled my headers. Anyone?

Outward
You want the wider non split end bearing on the header flange

When properly positioned as V2 mentions, the bonus is they're much more easily loosened. Gentle hammer blows distort the nut and pop the bonds loose more readily, plus shooting penetrating oil gets into the threads more easily and quickly because of the slits. On that note, one of my other cars uses copper plated nuts on the exhaust manifold and it's such a joy to find they always come loose properly.