Vehicle Registration Tax, the clue is in the name. There's no way you have to pay high VRT then get it reduced. If there's an option on the car it is subject to the VRT of the car/van it's installed in, not the original fitment. It does smack of typical MSL/MDL pricing policy, i.e. as much as you can get for as little as you can supply.
Toyota Ireland import their Landcruisers as passenger vehicles then get them converted. Revenue rules insist that all glass, seats and belts taken out of the cars must be "put beyond use". Toyota were scrapping over €3m worth of glass, belts and seats. The seats, in some cases leather, were slit open with a stanley knife. What a waste. Surely they could have been returned to the factory? Or the cars ordered without the fittings?