Looking good at this end. I'm sure that old impeller would have been "adequate" but the new one will last a few years and sure will push more water.
The Scotchbrite would work but would be way too much effort for me. Did you try using some lacquer thinner to wipe that white overspray off? Depending on what kind of paint the PO used it just might wash right off. I know MEK will take it off but will probably take off the white, original paint, your fingernails, and the hairs in your nose. That would be a job for outdoors.