I will be installing gutters on my 1936 Florida home in the next few weeks. I am re-painting the fascia - light sanding, priming with an adhesion primer, then 2 finish coats of latex. There are several minor areas (holes, joints)where caulking has been used and I would like to replace it with something more permanent. I get lots of rainfall and want to prevent rot as much as possible.

Would I dig out the caulk, and use something like Minwax wood hardener and performance wood filler? Or can I leave the caulk in the holes and then use the hardener and wood filler?

Or is there another method to repair minor damage to wood fascia that is more permanent than caulk?

Is there anything else I should do before the gutters get installed?

The wood fascia is nailed to the rafter ends - should I reinforce with ss screws also?

Thanks in advance for your insight!