You just have to wait for some sort of overtaking lane or for the truckie to pull over to let you past.
Rather than retrace our steps (which I hate doing) south down the Stuart Hwy and then east on the Barkly Hwy back to Barkly Homestead, we opted to take a much lesser known route that headed due east from Daly Waters on the Carpentaria Hwy and then south on the Tablelands Hwy.