Last week I actually had a friend who showed up with a trailer and went in to pickup my truck for me. The procedure is to email WWS in advance to setup a pickup appointment for the vehicle that got cleared by CBSA, with the driver name as my car carrier. As long as the cargo control number you are given by your Canadian import broker matches the papers they have at the port upon exit, it should be pretty simple...in theory.
But in reality, the port doesn't allow the public to drive into the import vehicle parking/pickup area, so my "driver" had to walk 500m back and forth between my truck and his truck when he discovered that the flashers of the imported truck were left on during the boat ride, therefore emptying the batteries and could not managed to jumper the dead truck with his truck. They made him walk back and forth a couple times lugging his spare batteries and tools. Just plain stupid. Nobody on site was helpful or able to communicate either. Lesson learned, best to assume that the vehicle won't start on its own upon pickup at the port, and no body will be helping you there as they might get a kick out of your miseary.