Opel and Vauxhall are brand names or "badges" of cars made and sold by GM or its sister companies. The Astra and Vectra models are sold by GM in different parts of the world using either the Opel or Vauxhall badges. In the Germany and the Philippines, it is known as the Opel Vectra while in the UK it is known as Vauxhall Vectra. The Calibra model was also sold under the Opel and Vauxhall brand in different countries.
under the handbrake
On the early "Vectra B" models it's under the trim immediately under the Hand-Brake lever.
under the front ashtray
under bonnet next to the batttery
if it has air condition it is behind the pollen filter under the bonet
On the cylinder head (gearbox end), under the vacuum pump.
16 pinconnection can be found under plastic cover directly under handbrake
It's under the right hand side of the steering wheel.
at the back of the engine, under the bar near the top of engine
it should be under the right hand side of the engine cover!
its on the oil cooler /filter block thats right under the alternator