As I wrote in the other thread, there is currently nothing in the category Category:Neapolitan_War that is relevant to the Neapolitan war. So we have two options:
1. Rename that category into Category:Napoleonic_Wars, and if needed re-create a new category for the Neapolitan war.
2. Create a new category Category:Napoleonic_Wars, and move by hand everything that is currently in Category:Neapolitan_War, including the FSP.
It seems to me that solution 1 would be much faster, for the same result. The only advantage I see to solution 2 is that the change history would be more understandable.