Corrosion or tarnish — what to do
 

What would you do to this trigger guard to make it look better?

Guard
 

What I did to one of mine.
Ballistal and Fortier pad.

Apart from cleaning it and removing any actual active rust, there is not much you can do to make it look any different. Just rebluing it.

Exactly the advice a vintage knife expert would give a collector.

If aggressive polishing is resorted to, e.g., as per a buffing wheel, so as to efface corroded metal, it is a dead giveaway that something incalculably ugly had been there. The imagination runs wild.

With the active rust removed what remains is a cared-for object, with character.

I've heard of everything from Flitz, Big 45 Frontier Metal Cleaner, 0000 steel wool, WD 40, baking soda, to Bar Keepers Friend ...

I'm not looking to polish it -- just get the active rust, if that's what it is, out. It's more like tiny spots of corrosion. I think the engraving would look better without it.

That looks good to me. Maybe others like the patina look better ...

Ron:

The active rust is red.

Take Scott G's advice, it will not harm the guard and leave it with it's original finish.

Unfortunately or maybe in this case fortunately I'm red / green color deficient

A Google search for "Fortier pad" yielded zero results