As i recall there are several friction type fasteners around the perimiter of the panel that can be removed by prying carefully away from the metal portion of the door to free up the trim panel.
Toyota hiace door handle removal.
Slide the door handle toward the rear of the vehicle and pull it out.
This bolt holds the lock cylinder and handle in place.
Open the sliding doors then use the inline socket to remove the bolt in front of the track s cover.
Detach the rubber access plug on the edge of the door and loosen the bolt behind the plug using a torx wrench.
Close the sliding door of your hiace van.
Be careful not to drop the bolt but if you do you can retrieve it using a magnetic tool.