One option to use that I did was to scrape off the original finish. I removed the wood pieces on my 336 because the factory finish was pretty "tacky looking".
I know not all Marlins had this blonde or light looking wood with some sort of factory applied glossy looking overcoat on it.
I gave mine a rustic look. Scraping it all off with a sharp pocket knife along with some stripper then refinishing with a dark walnut stain and tung oil.
A little elbow grease with fine steel wool and I have a pretty nice looking rifle. Scuffs, dings or scrapes on a finish like this only add character to an otherwise sort of old & used piece of wood. My choice of wood finish on my 336 is sort of like "timber framing" or " log cabin" if you know what I mean. It's not pristine with a gloss shine. The guys at deer camp sure do admire it when passed around by the firelight.