Been reading up on EOH, sounds good as can use the hubs I have and save there.
Thinking again such a long trailer is not much use except when carting the two cars. Why not make a 5 metre bed as say a normal carrier then have a 1 metre extension either clip on/slide out at the back and another 1 metre extension over the draw bar. Probably does not need the full metre as its only for the wheel tracks.