See also post about moving the hood release lever to the left side.
Unlike most sedans, the Jaguar XJ6 front bonnet opens from the back (near the front windscreen) and pivots up towards the front of the car. A safety hook keeps the hood from popping up too far upon release, and the bonnet is secured to the chassis with two striker pins.
The striker pin resembles a coil-over shock absorber; a fixed center bolt with a special conic-shaped tip is surrounded by a compression spring. A bottom lip catches on a sliding latch bolted to the chassis and this slider is attached to a cable operated from the cabin. A pull on the cable moves the slider about a 1/4″ and thus releases the bottom lip of the sticker pin. The slot in the conic tip is used to adjust the height of the pin with a screwdriver.
That’s the theory at least. The system is somewhat complicated and the components tend to be fragile and finicky.
Fortunately, there is a back-up method of releasing the sticker pin in the event of cable failure; a small hole in the wheel well just below the latch makes it possible to insert a screwdriver and push the slider back to release the pin.
It is critical to align the pins correctly so that the hood lays flat but isn’t forced into position. Trial and error is the only way to get it right.
Setting the pins too high (that is, not threaded into the underside of the bonnet far enough) will result in the back of the hood above the windscreen chassis edge.
If the bonnet is then forced down, there is a risk that the pins will become lodged in the latch because they are misaligned (not straight in as intended).
When the height of the pins is correct, the bonnet lays flat against the chassis and the latch will pop the hood up upon the release of the latch slider.