1951-53 model year K-F cars have "wartime chrome" which is chrome bonded to the metal directly, there is no copper "middle" which would produce better bonding. Unfortunately, pot metal and weather are the things that destroy chrome over time. The pot metal is riddled with tiny pockets of air or gas and when the metal warms and cools, the pockets tend to "move" to the surface and break through the thin chrome. This creates the pock marks you see and allows moisture and crud to oxidize the metal causing the rust (top down rather than the bottom up pock marks).
The only thing you can do is to replate the chrome. NOS CHROME FOR CARS OF K-F VINTAGE IS IFFY AT BEST AS THE NATURAL CHEMICAL ACTIONS I HAVE NOTED ATTACK THE MATERAL EVEN WHEN WRAPPED OR BOXED...it only deteriorates a bit slower if the stuff is kept in a dry area with little temperature fluxuation.
