Actually, looking at the pics again the bonnet scoop is quite wide. Wider than most I've seen. The most likely UK kits would be Pilgrim, Corbretti or Dax, and the pilgrim had a narrow scoop, whereas the Dax was more like yours.
Did you say it had Jag front end? That was usual for Dax. Maybe you take it round to JBs and compare!
Of course this is assuming it is UK.
PS: you've done well if your did score a Dax! Nice cars.
Here is the factory demo Dax:
