If you can track down the bloke who programmed the ecu - you could probably get him to write the needed code for a slab or two.
it wouldn't surprise me if the code isn't already in there and all that's needed is wiring up a couple of switches and enabling the function - more than likely LR left the option out for marketing reasons.....
If you ever meet someone from a marketing department - give 'em a slap to the head, they do deserve it.

