I don't think it was entered but was just a supporting vehicle, joining in and doing the run.
See more of the entrants pictures here on the excellent Nick Spencer's Flickr file
On e-bay currently is a J van back.
MORRIS J TYPE BODY REMOVED WHEN VEHICLE WAS RESTORED SO NOT REQUIRED EXCELLENT CONDITION FOR AGE AS YOU CAN SEE FROM THE PICTURES, GIVEN A COAT OF PAINT TO PROTECT THE SURFACE FROM RUST - ITEMS LIKE THIS ARE SO RARE AND HARD TO FIND. PERFECT FOR RESTORATION PROJECT OR AS SPARES FOR A COLLECTOR. I BELIEVE THIS VAN WAS ORIGINALLY A PLANNERS VAN BUT CANT BE 100%.