Games : What are the prerequisites for changing government in Europa Universalis IV?

I am currently playing a game as the Iroquois Nation, and I have:

1. Completed all native ideas


2. Have a number of provinces bordering a westernized nation (France to the North)


3. I have the Conquest of Paradise DLC installed and active.


4. (Possibly Irrelevant) I am independently at level 6 administrative tech.

As you can see in the screenshot below, despite the above I still cannot change my government type. Does anyone know why or what the complete list of requirements is to change government types as a North American nation?