Can’t see your bumper very well on my poxy phone, but the parking sensors are built into the black centre outer trims and the black fog light trims, you can buy an upgrade kit, I had to buy a front and rear kit with fog trims. I didn’t use the wider mount in the centre trim as I have a start line bumper so just used my PDC hole cutter kit and it looks fine, but more importantly doesn’t affect its operation. The trims are marked on the back so if it were mine, I would just fit the smaller mounts.
I have a brand new set of the centre trims but you would need the sensors and swap over the red piping trim.
Looking at it, it should be doable. The sensors go to the PDC ecu. If you have rear sensors already the ecu will need to be replaced with an eight channel unit. The sensors plug into the PDC ecu not the head unit (5F). Distance info is shared on a bus network.
Nice van!