My butt just puckered for you in case yours went numb with that newsI happened to be at a Chrysler dealer for unrelated reasons (wife's Charger), so I asked the parts counter person about my situation. He was quite informative.
He said that the block is not actually welded to the axle, but is held on by the vent tube bolt. The back edge is just machined to match the axle tube's curve. He also told me that the brake line with that block on it costs about $260 to replace. Also that the bolt/vent tube is unavailable anywhere and no dealer on the country has one (so don't break it).
Good times