It should be possible to configure a model so that its inventory can only be accessed (by a player) by interacting with a specific widget or other component of that model, as opposed to being able to access that inventory from anywhere on the model. That access point may also be concealed behind a movable cover (like a firebox door on steam locomotives or a cap on a fuel tank, for example).

Expanding on this, it should also be possible to configure specific inventories for each of these access point components, instead of being limited to one global inventory for the entire model.

Aside from the immersion/realism aspect which could be applied to many existing and future models, this would also have a number of practical applications in the future including:

• Separate fuel/firebox inventories for tank engines
• Multiple fluid inventories for liquid-fueled steam locomotives, internal combustion locomotives, partitioned tank cars, etc.
• Having both private and public inventories on a single rail car

This would necessitate a change in how loader/unloader augments/structures work (or will work once they are overhauled) this change could involve having to position the locomotive/car in a certain way so that the input/output device lines up with the inventory access component, or by configuring the input/output device to interact with a certain inventory component.

The IR config could also have the option to forcibly override this feature for all loaded stock and use the old inventory access method in all cases. I am not sure how this would work; perhaps all separate inventories on the model would be accessible from the same interface if this setting is enabled.