My guess would be he got about 5 passersby to lift it for him while he jammed the wood in there. Then they carefully wiped their fingerprints off the vehicle and skipped town to avoid liability.
I think he is holding up the truck with his head. The posts are only there to make it look “safe”.
The photo provided by @kurtwm2010 above reminds me of Francis Drake – the 1500’s infamous British naval-officer, some say “pirate”. He ran into a little trouble during one of his trips and had to do the same thing when he got a leak in his boat while exploring the west coast of America. To expose the leak, he parked & anchored his boat in a tiny bay north of San Francisco – now called Drake’s Bay – and tied ropes from the top of the ship’s mast to some trees onshore. Then his crew pulled on the ropes to tip the ship completely on its side, exposing the bottom and the leak.
So that fellow under the blue truck, maybe he’s actually an intrepid world explorer for the Crown … lol …
Well he doesn’t look British but who knows? What does a Britain look like anymore anyway?