/stupid question
I've never actually replaced the HID bulbs before, best to disconnect battery? Considering changing that anyway, as it's turning over a bit slow now. Winter kicking in.
Even with your gadget hands, you will not get in the OS one without removing battery. So non-issue.
Check adjusters before you buy bulbs, if they are broken, buy some, and do all at same time.
Not actually tested adjusted before
Pop off rubber cover for main beam bulb/sidelight/euroland adjuster, and grab back of bulb holder, and move unit in and out. Will be blatantly obvious if adjuster is broken.
I can pretty much guarantee at least one is. Don't piss around, replace adjusters on both.
Bit fiddly to do, pop it up and watch Mrs TB and I do one, then you'll be fully confidence. The big thing is not to get any of the sealant onto anything visible, as you won't shift it.