12v feed from main beam

Hi. What's the best (maybe I mean easiest rather than best!) way to get a 12v feed from the main beam to run to a light bar solenoid? It's a 2014 Freelander 2, and the light bar will be on the grill - hopefully so I see the deer before running into them...
Also, if anyone's got any tips for getting the switch wiring through the bulkhead, and where best/easiest to install the switch. Beavis Pits has a YouTube video on each - should I just follow his suggestions? I think his is a pre-facelift model - is the bulkhead going to be the same? He puts his switch on the overhead panel, but I'd rather it on the dash.
Grateful for any advice.

First off, does it have just a single bulb for the head lights, which does double duty as the dip and main beams? I'm assuming so as you're wanting better main beams.
With the single bulb system, the main beam is controlled by a shutter in the headlamp assembly, which simply moves out the way when main beams are needed. This shutter is powered by the CJB, and can be used to power a relay coil for additional lighting.
Personally I'd not bother with running cables to a switch inside, as I wouldn't be fitting extra lights if they weren't needed, so why turn the extra lights off?
When I had my light bar on my FL1, I had it coming on with main beams all the time. I'll do the same when I finally get round to fitting it to my FL2. There's been no rush for me, as the earlier FL2 has much better lights than the facelift models.

Thanks. Yes, it's a single bulb doing both main beam and dip. I don't really know my way around it, but I'm sure I can hunt out the CJB.
The main beam is fine generally, but living in remote NW Scotland, red deer are a real nuisance on the roads at night, and hitting a big stag at speed can be expensive (but the FL has proven surprisingly tough - whilst other vehicles are write-offs!). So, the light bar is to flood the road and roadside ahead with light to help me see and avoid deer. I use the FL for work, on my commute, often at night, with no other traffic on the road. I want to be able to disconnect the light bar if I'm driving where there may be other traffic, as it's a bit too powerful if I catch people unaware - hence me wanting a switch inside.

The electrical connection for the relay can be taken at the lights or JCB, but you'll need to identify the wires needed to trigger the main beams shutter.
I've no idea how to get the wires through the bulkhead, but I'm sure it's not easy.