I had mine that clean during the rebuild but now its muddy as he!!. My pump cover was just as faded as yours, so i took some straight 2 Stroke oil and rubbed it on there, Looks 10X's better. Just a tip. Great looking blasty.
And then you get it muddy and get all pissed off. haha
I just cleaned mine and took it out for jetting but it's been so damn wet in Ohio that it was inevitable it would get dirty. Luckily I coated the whole thing in armor all and waxed the frame so it all wiped off with a rag.