Late '76 I would guess.
My ACG3115 was registered 14th October '76 - not sure when built though. My slightly earlier car (ACG2367) was registered 2nd August '76.
Cheers Paul,
1976 TR7 FHC, ACG 3115 - Java Green (on the road)
1976 TR7 FHC, ACG 2367 - Carmine Red (on the road)
1980 TR7V8 3.9 DHC, Orient Blue (on the road)
1977 TR7V8 3.9 FHC rally car, ACG 35005 - Tahiti Blue (complete, no MOT)
www.TR7.co.uk