I have the same valve cover with a similar situation. I haven't addressed the problem as yet, but assuming that you can determine a paint that is compatible with aluminum as well as being resistant to gasoline, oil and heat, it's a fill-and-wipe process. Paint is first generously applied to the logo area, after which the excess is wiped off the surrounding surface. Google fill-and-wipe painting, there's lots of DIY stuff out there.
Note: Best to remove remnants of the old paint first and thoroughly clean the surface.