To make it road legal, you need headlight washers.
Auto levelling is not requred, as all e46-s have manual headlight levelling wheel you can access from drivers seat.

Snip from NCT manual:
Where a levelling device is mandatory, the levelling device is not operating or manual headlamp levelling device cannot be operated from driver’s seat.
You need new wiring loom for headlight washer pump and a K6 relay for it. (Sky Blue relay)
Relay part number is 61366915327

K6 relay connects to 30A fuse F51 in glove box and to general module X253 plug pin 12.

Coding is required for it to work.

You also need headlight washer pump, hoses, spray jets and the trim bits under headlight.
Washer bottle has a slot for pump, but needs to be drilled.

Fitting the hoses for washer is hardest part.


As for lights themselves.
If you want bi-xenon to work, you will need to get the loom for it, but otherwise the lights swap straight over. (I have done pre-facelift vert and facelift saloon. Don't know about facelift coupe)
I didn't bother with bi-xenon and was happy enouogh with standard hi-beam and xenon low-beam.

Coding is needed to stop lights strobing when engine is on.

I did it years ago and don't remember exact details, but fitting lights was the easy part. Washers was where I spent my time on.