I saw your fieldnote, Hamish, and thought 'how on earth can they know how it used to look (and therefore, wouldn't it be totally inauthentic to try and recreate it)' = but, isn't that interesting that there are lots of sketches in existence of the stones, dating back 200+ years. It can't be every cromlech that's been so well documented. Still going to be a bit tricky though - the cromlechs I've seen have looked so well/finely balanced you can hardly believe they're standing anyway! good luck to them I think.