Automatic upgrade vehicles

Now we can manually set a vehicle to return home to upgrade, it would be great if we could set the vehicle assembly to go through and replace all vehicles with a per vehicle toggle.
Additional ideas
Per mining tower/building
Per type eg: in Vic overview upgrade all unassigned trucks

I think tied to a building would be the best implementation that way you dont get trucks that are bound to your fuel station getting upgraded as dumpers or ones attached to mining upgraded as tankers, however upgrading from pickup to truck it finds one automatically and replaces it