I would say....:
1. If you can sort it out from the instrument cluster menu as suggested, then great.
2. If not, you may have a case against the selling dealer under the Consumer Protection Act 2015, the goods are both 'not as described' and 'not fit for purpose', as long as you have proof that you explained to them that you needed the car to be legal in France, in essence try and get them to fit EU headlamps at no cost to you or (threaten to) take them to court.
3. If neither 1 or 2 above work for you, the only people I would trust with this conversion are forum members Richard and Alfie at
www.comandonline.co.uk in Lightwater in the UK (SE).