The Farnborough Watchman bought under the MOD contract was mounted on the concrete tower (much taller than the 'standard' Watchman tower) originally erected for the AR1 but initially there was some problem with the mouning plate and the tilt was wrong so the scanner had to be removed and a new mounting plate manufactured and installed.
When it eventually was available for operational use (1991?), it served us well (although its coverage wasn't as good as the AR1 it replaced) until it too was replaced by that horrible Raytheon ASR10 in November 2002 which was nowhere near as good as the Watchman.

En route variant
 

Did you know there was an en route variant named the "Routeman"? As a spotty grad in the 90s I forgot which LRRS I encountered it at. Maybe Lowther Hill in the southern uplands. I tend only to remember the 23cm at Claxby, Lincs. Mainly because I met the nicest ever Sen Engineer there in charge of the whole site- Tony Lowe I think his name was. And the station Administrator Elaine. Made the best cuppas ever. They let us climb up the gantry with this massive rotating antenna, like the Heathrow one, only all white, what felt like inches (mm) above our heads... on a bright sunny Lincs day with nothing else around, very memorable.

I always though Claxby was made by HSA, not Plessey.

Absolutely... my point was I couldn't remember where I'd seen the Routeman because the HSA had dominated my memory, that's all :-)

Lowther Hill and Perwinnes had the Routeman until replaced by Raytheon ASR-23SS about ten years ago.