I’d advise caution media blasting these parts. Neither the distribution block nor the proportioning valve have a rough finish and once you media blast them it is challenging to carefully remove the texture you’ve created on all faces. It is the quickest, easiest way to make them look shiny to post on eBay, but you are creating work to remove the media blast finish later. Shelbymann70, you and others may have a refined technique, but your average joe blasts the crud out of them and makes it hard to get these back to factory look.