These seem to be relatively easy to get level with the FW bodywork – not sure how it is with the standard nose cone. There’s a feature line extending almost to the front of the car. You take a measurement down from this and an amount away from the front and hey presto. I wired them in with the bonnet fully open so there would be enough slack in the future.
It might not be obvious on the photo but I accidentally put the passenger side unit in the holder so the lense wouldn’t be level. Time was pressing though so that will get looked at later.