Hi mudhen
If it's any use the Boscombe show report in British Aviation Review June 1990 lists the Vigilant thus...
ZH125 Vigilant T.l ACCGS "Gauntlet 14" Syerston 7.6 [arrival on loan to A&AEE/A Sqdn]
and the same report also has two Me109s/HA.1112MILs as being present for the show - one of which was D-FEHD
- 14 Me109 (HA.1112MIL) Private "GHUNN" Roundwood 8.6
- 15 Me109 (HA.1112MIL) Private "DFEHD" Goodwood 8.6
[both departed each day after the mock battle]
It also adds the following...
"The Hurricanes, Spitfires and Me109's were all scheduled to take part in a mock battle
at the end of the display each day. However, strong winds forced the cancellation of
the battle on 9.6 (and the rehearsal on 8.6) but it did eventually take place on 10.6."
Re the codes you have quoted on both of these, the 109 was actually wearing '15' rather than '12' & at the time ZH125 had yet to be coded 'TL'; See...
https://www.flickr.com/photos/chrisengland/18975190612
https://abpic.co.uk/pictures/registration/ZH125
While the owner of the 109 isn't listed in the BAR show report, Geoff Goodall's Warbirds Directory has the following data on that particular machine, and its owner at the time of the show...
---------
213 • HA-1112-M1L C.4K-40 Tablada AB, Spain: inst. airframe
Hans Dittes, Speyer near Mannheim West Germany .80/86
rest. Mannheim, ff .86 in Luftwaffe scheme
D-FEHD Hans Dittes, Speyer 29.8.86/95
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Best wishes