Car On Gas (Morecambe) tell me they are converting petrol Range Rover Sports for £1495 + VAT with all the cetificates and a lifetime guarantee and there's no reason why the SC can't be converted.
They specialise in Land Rovers and are fully booked for 3-4 weeks on conversions.
I have used them to convert a Range Rover a few years back and could switch from petrol to gas and not notice the difference.
Gordon Brown was talking recently about reducing road tax for lpg converted vehicles and apparantly they are already exempt from the London Congestion Zone charging, . Now that would upset the anti 4x4 brigade!

You can contact Cars on Gas on 01524389500
Have a chat with Stuart, he's quite clued up and not a 'greenpeace' type but a Land Rover, 4 x 4 fanatic.

i will do thnx