What's On These Head Bolts?

If it doesn't lead to an issue, suit yourself, to eschew his own, etc and so forth.
Anything going into water I put rtv or thread sealer on the threads. The rest is wire wheeled and just lightly oiled.

OP has a rookie amount of sealer applied.
You put it on the threads, wipe just down the thread edge ...so it doesnt get in between gasket ...or smeared everywhere.