Setting up HA with already existing configured opnsense

[Com_DAC]

I've got an instance of opnsense that has been running without issue for over a year now. I'm wanting to add a second one in an ha configuration (carp). I'm wondering how I should start with the second one? Should I set it up with a restore from the existing primary or should it be blank with minimal configuration and let the sync process set it up?

Thank you.