Hi Russ,
I know this isn't the 'UK' you're referring to, and it isn't about church organs per se, but I thought you might find it interesting nonetheless.
http://www.cinema-organs.org.uk/UK%20ORGANS/ukorgans.html My father was intrumental in the construction of the Compton organ in the Gaumont Cinema in North Finchley, North London in 1938. The building has long since been demolished, but the organ lives on at a little country pub (at which a special extension had to be built to accommodate the organ, plus a small electricity sub-station to be installed) about 30 miles north of London.
Those old theatre organs were certainly something to behold.