How to select subtype of the van from python?

I have with pyton,
```

ego = Vehicle(
"ego",
model="pickup",
license="GREY",
extensions=["vehicleEngineCode"], # only this way the vechicle code can be loaded.
color='green',
part_config='vehicles/van/h15_vanster.pc'
)
```

but this DOES NOT load the "van" skin, it clearly has the same, default skin,

what can I do to load the other van skin?