Not sure if this is anything to do with it...Gun laying radar, some GL Mk11 units were sent to Russia and some GL MK111 units were too according to these two Wiki articles, not had chance to research further to confirm anything either way (Mk11 mentioned in the Mk1 article):
https://en.wikipedia.org/wiki/GL_Mk._I_radar
https://en.wikipedia.org/wiki/GL_Mk._III_radar
EDIT: Apparently the display tubes were 5" or 6" so not the same as Andy has, never mind, there may still be some kind of connection somewhere.
Lawrence.