You'd need to support it in 3 places wouldn't you? So that it doesn't fold up in the middle?
If this is a one time transport, I'd use a flat deck. If you are wanting to move it around every harvest, multiple times, then I'd be looking to buy/build a trailer that can handle it.
That's what we did. Seems like we put the straight cut headers on and then jump from field to field cutting wheat. When we are done cutting wheat, the pickup heads are many miles away. So we built a trailer that can carry two JD615P heads at once.
Andrew