Your example is shared currently by the dissipation of Toyota assembly plants across the US. No one in these plants manufactures anything, they just put parts together from a central manufacturing area.
This is exactly what happened in Puerto Rico.
Because these plants are self sustaining from parts made in mother plants, there is no requirement or opportunity for smaller companies to move to the area and manufacture the parts neccessary for the finished goods.Which is why these assembly plants only attract service industries.
Moreover,the opposite occurred in the hay days of Detroit, the car companies needed supplies of headlamp bulbs,nuts and bolts,tires,dynamos,windshields,etc,etc. These components
were manufactured locally by smaller companies.