Whups! Eyup Tim and Baza, I missed this till now. I've made a mistake.
"Hob has posted Caer Bach on TMA at SH744739"
I'm an idiot. It should be SH744729. It's definitley not Cerrig y Dinas. Cheers for leading me to that Baz. In me defence, I think it was the thing I ever posted here ;)
It was me that contacted Tim last year, I'm chuffed to see that pic. The stone shows up lovely. I caught it by full moon, just after sunset, and it seemed to glow. I could hardly make out the mor elocal looking stones by comparison.
The nearby 'healing' well in the yard of the old chapel near Gardedd-Wen (SH451737) is canny. I recall a suspiciously upright stone next to the tree behind the chapel too.