When we got our Lightnings on 92 we had a very large towable test kit
Had a similar thing on F4's. Spent three years on them and I think I took the cover off it once to see what it looked like.
I left in '96 but as a member of RAFFCA I started flying three years ago from the last unit I served at. My how things have changed...apart from the aircraft of course, they are exactly the same ones that I left bereft of my technical knowledge in '96. It's a totally alien Air Force to the one I left and might as well be from another galaxy cf the one I joined on May 14th 1974. 40 years ago this Wednesday. Scary.