Do you currently have Bi-Xenons on the low beam side of the lights - if so you will already have Xenon Hi/Lo Beam - the halogen hi beam is just a filler beam like other Bi-Xenon equipped Landrovers.
But to your actual question - not a FL2 but a RRS - I have put in HIDs into my high beam (mine have H7 globes and I would expect yours to be the same - check your handbook). The globes straight in and I was able to bit the ballasts in the light housing.
The main issue putting HIDs into your hi beam is that it takes up to 10 secs for the lights to get to full brilliance and headlight flashing from cold is not good.
When I turn my hi beams on from cold I get an initial flash then the lights slowly come up to full brilliance - initially blue then the other colours come in ending in natural white. If the globes are warm then the lights come on to full brilliance immediately.
You need to confirm your globes and buy a canbus compatible kit - the best heat range to get is 4300K.
Garry
REMLR 243
2007 Range Rover Sport TDV6
1977 FC 101
1976 Jaguar XJ12C
1973 Haflinger AP700
1971 Jaguar V12 E-Type Series 3 Roadster
1957 Series 1 88"
1957 Series 1 88" Station Wagon
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