NoPax,
Inside the tower at Henlow was unpainted in certain places and you could clearly see stencilled things like: 'Hurricane starboard wing', followed by a reference number.
Back to the TSR2 for a sec; the terrain following radar, designed by Ferranti in Edinburgh, originally took to the air in a Dakota, TS 423, which still flies today. The funny thing about using the Dak was that the terrain climbed faster than the aircraft could!
The radar was then tested in a succession of Canberras and ultimately in the second production Buccanneer, XK 487, which hurtled about the Scottish Highlands as low as 200 feet.
I have a pic but can't post it just now, because PBase, my photo repository is down. Check back later.