Full sheet of plywood is 250cm long. That truck has a 150cm long bed. You're going to need roof racks or a trailer anyway. I know because I regularly haul full sheets of plywood and plasterboard with a pickup truck that has a 180cm long bed. Leaving the tailgate open doesn't help much either because while the bed technically is wide enough for a full sheet, in practice it's not because of the wheel arches on both sides. It wont lay flat and is quite hard to tie down.