All the shining in the world will only last for weeks, sorry but thats a fact. You see this evil magnesium oxidizes from within the metal, not from the outside inward.
You can seal it with whatever but it will return to gray.
I tried to clean mine up, I masked off the VC and used 600 grit and made a great mirror polish, looked absolutely fantastic. I kept it clean and tried several things to keep the VC's nice, NOTHING worked.
I was even told by a metal polisher that it could be clear coated and may last several months but it would have to be repeated and re-coated continually.
MOJO, if you could channel your resources into making an aluminum/chromed VC for the snake that was reasonably priced you'd make money.