Must be 1991 at the latest indeed.
On 13-10-1991 (almost its 20th anniversary already...) a farewell photo call was held, because of the imminent closure of RAFG Wildenrath. Highlight of the static display was one of the last "operational" EE Lightnings, operated by BAe Warton as a chase aircraft:
The Wildenrath Phantom squadrons had of course a Lightning history, the base however did not (the squadrons were at that time based at RAFG Gütersloh) apart from some Lightnings used as decoys during base exercises in the 80's. Being much younger back then, at one time we had much fun when Lightnings coded K, U and T where neatly lined up, visible from the public road. This photo shows the K and U in September 1984. A third example (the missing "T"?) is just visible under the shed:
Good memories!
Cheers,
Marco