So looks like previous owner had a bit of a cheapskate paint job on my 2017 Fit (lots of over spray, looks like nothing was disassembled only masked off), and I was noticing there's some rust forming under the antenna mount base. Would just putting a shark fin and sealant over it be a good way to mitigate? And if cleaning first will be necessary, does that mean sanding or will something like evaporust work and not damage the paint (they say it wont, but not sure for automotive use)?
Thanks.

 

Oh, off topic but is there a way to make images not be massive like that?

 

Can you please share the clear image.

 

I would remove the antenna base to see what's underneath. Lightly sand loose rust off and then apply an anti-rust primer and then some top coat. Allow to fully dry and then remount whatever antenna base you want. You can't just seal the rust in and leave it as is. The rust will continue to eat away at the metal