>By my reckoning this is 52°43’41.19” N 002°59’42.67” W. I think this is in Wales ... just.<
Indeed it is -- just over the border. The actual co-ordinates are N52°43’42” W002°59’48” (or in decimal 52.72842N 2.99677W). Failing that, SJ 32790 14987 (OSGB36). The UTM is 30U 500225 5842050. It's in LFA9, but Shawbury Low Level is on 376.675 and Ops is Extn 7227 (DFTS 95531).
But no RAF aircraft will ever find it . . .