Rod,
I can't help you with your questions, but you reminded me of an Air Clues article from the 60s. There was a fleet of Vampires and Piston Provosts at Shawbury that was used to provide targets for trainee ATCOs. To handle the load, a GCA radar was installed at Sleap.
The Air Clues article was pointing out how busy Sleap was - I think there were more GCAs at Sleap than any other UK airfield.
The title of the the article was Don't go to sleep when you go to Sleap.