Anything with wheels and an internal combustion engine is welcome; cars, trucks, motorcycles, buses, even tractors 
Well saying that... are tracks allowed? Cause me and a friend have (jokingly) toyed with the idea of driving to EF in a tank 
1) You'd need rubber track covers for road use
2) I doubt you'd find any insurers that would cover you for that long a distance road use in both the UK *AND* Europe
3) Have fun trying to get one on a Ferry, as you won't fit on the Eurotunnel

4) I hope you've won the lottery to fund the fuel costs
Nice idea, would be fun to see, but I'd advise against it, tbh. It would require a lot of forwards planning with authorities, which you really don't have the time to do now.