In a top quality plate the tanks first gets a copper sulfate treatment, which yields a 100% copper cover ( no Faradya's cage effect )
Next it gets an electric copper followed by a polish. This breaks up the grain structure which prevents excessive dendritic deposition of the nickel.
If you break through with the copper then you do it again, and again, and again ( get the picture).
Once you are happy with the surface then you can add the nickel.
The number and depth of each coat will have a major effect on the final outcome.
Modern plating uses chemical "brighteners & flatteners" both of which yields a some what thin looking plate.
Quality plating will polish after each thick nickel and finish off with a flash chrome followed by a thicker chrome.
Usually only places that specialise in restorations or HD's will do this type of plating.
It ain't cheap as there is a lot of labour in the process.
The center bumper of the Shadow was over $ 1000, each end was around $ 1500 and the over riders $ 365 each.
The good bit is that they will last for another 40 years out in the weather ( provided that I give them an occasional wax)
