In theory if i buy an EU3 - could I ship the car back to MMC when I head back to France and have them convert it into an EU4 ?
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I think you need to keep it as an EU4 and plan for a Stage 1 kit for EU4 at some point! OR get some advice from our Gallic 3 wheelers as to whether officialdom in La France is likely to care at all about EU spec status when you re-register it there... it might be that a nice bottle of Bordeaux "smooths" the certification process!