I see in your introduction that you have been reading about BM for a couple of weeks, and you are obviously hovering a meter or two above ground. That's wonderful! But now you need to calm down and be realistic again.
Basically, if you have to ask, you are probably not ready to bring a Mutant Vehicle from England.
But as a brain exercise, I see two ways to go about it:
1: Build it in England and have it shipped directly to BRC in a sea-land container.
2: Design it in England and build it here. That would mean moving here long before the event, renting shop space, buying tools and materials and so forth.
Container shipping can be surprisingly affordable, so that would be my first choice. Too many variable with building it here on short notice. But either way, it will cost real money.
Once you are back on the ground, consider whether you really have an idea that "must" be built. I'm learning that just because I have an idea, does not mean I should try to carry it out. I must concentrate on what's doable.
Does this make sense?