If I take out the complete headlight unit (think my HID bulbs have gone dim over time) will I have to get the beam set up again or will the headlight fit back in exactly the same position.

You will I am sure struggle to get the lamps to line back up in the exact position they were in so technically yes, in reality you probably just need to manually adjust the Dipped and Main Beam Adjuster's to get the beam pattern at the right height projected onto a wall for example.......

As long as the lousy Hella adjusters haven't rusted up - the gears usually end up loose and useless on the shaft.

rotodiesel.

Thanks for the replies.