I have one way, but feel like there's got to be a better one. If you choose ignore artboards they all print on one page.
Here's an example:
I have a 42in roll in the printer. I have a 3 artboard document 20x11. The most efficient way then would be to print them all rotated next to eachother (or actually I'd stack them and rotate the paper instead so it's less of a headache).
I can export to PDF and print from acrobat, but there's no option to Not scale the document when you print multiple per page.
Is there another way? Ideally I'd like trim lines on each artboard as well for pages that have any white edges.
I'm getting by, but I'd love to learn something better if it's out there.