Sounds much like we found the same pile of rocks then Chris. I don't remember where it was in relation to the fence, but sounds like the spot I saw.
I went back to the website where I read that Bradup may have been destroyed... and found it was yours! Also followed your link to Paul Kenyon's pic, and I'm pretty sure that's not the place I thought was the circle. So, it's looking bit grim for Bradup.
I hope to get back to Yorkshire n' up on the moor earlyish next year... so I'll go over to Rivock Edge while the weather's still too cold for bitey things n' have a wonder over. Or maybe next time Moth is up that way, he could have a quick gander... I'd be interested to hear if it really has gone. Moth's Mission... sounds a bit like Challenge Anneka!
The stones at Rivock are notoriously hard to find. Covered in loads of pine needles in a dark wood. David Raven has a couple or so decent pics on his website...