All Trophys come with the bog standard halogen units. To swap them over is a simple plug and play swap however bare in mind if you source 172 xenons you need to take the headlight adjuster motor from your halogens and fit it to the 172 headlights. They changed the design of the motors plug socket between 172/182.
No Trophy had factory-fitted Xenons as far as I'm aware.
To retro-fit them I think you need to remove the bumper then the lights are just a straight swap. More than happy to be corrected, it was a long time since I did mine.
^ Not quite. Headlight washers have to work if present or its a fail; so if you dont have them they cannot be tested and therefore you pass. Have a read:
dipped beam headlamps may be fitted with headlamp washers and a suspension or headlamp self levelling system. Where such systems are fitted, they must work;