Something else to then.
The best attribute of epoxy is the bond and barrier it creates between the metal and what ever comes next.
Two coats are the recommended thickness. Three is bomb proof (more or less)
But what happens when you start sanding down filler or high build?
You hit high spots and start sanding on epoxy.
Now it's not 2 coats thick anymore.
My solution was by black and white epoxy (from spi) and use one as my first 2 coats then mix the rest as needed/desired to my needs.
If I lay a third coat over the white/black I know to stop sanding as soon as I see that color shows up.
that 3rd coat can go on down the road, all the epoxy will need is a good scuff with a red scotch pad (320g).

Give me ambiguity
or give me something else