Car appreciation... the aesthetics, the engineering, etc

Chaps would anyone be able to give me a little help or guidance here?

I have a 2007 Land Rover Discovery Commercial and I hated the stock cloth seats, genuinely uncomfortable back breakers and I do about 100k km a year so not good.

I've swapped in a set of BMW E46 seats in red leather and made up the appropriate adaptors to go between seats and bases and they fit great and are super comfortable. Here's my problem though...

• I can't figure out how to wire the BMW seatbelt pretensioners to the Land Rover wiring loom.
  
• I can't figure out what to do with the Land Rover loom to "blank" the side airbags that used to be in the Land Rover seats but aren't in the BMW seats. Thus I have a permanently on airbag warning light which is pretty annoying and means I have to swap the seats back over every year for the DOE (Irish commercial test)...
  
  

Any ideas on where I could find this information? It can't be any more difficult than finding out which wires to splice together for the pretensioner surely and then providing some sort of resistance in place of the airbag sensor?