Hi brookes, I was wondering the same thing as I'm going from single to tandem. In the past I've had some various thicknesses of wood, thickest being a 50mm sleeper. As you probably know small adjustments across the axles can be done with the drop jacks. I've seen a bloke drive off the top of those yellow levellers instead of back down and smashed them to bits but I don't know what brand they were. I was also wondering if the levellers cover the width of the tire on the outbacks?
Cheers.