Spray Chrome

In tests, I got a shiny surface using a spray can of Krylon Silver Foil Metallic, available at hardware stores. Much better than the old "bumper chrome", though not quite as shiny as real chrome. I tried on a plastic dash piece, after thoroughly removing the peeling chrome to bare plastic by soaking in Super Clean. The trick is to spray a very thin coat, as the can says.

However, I tested the cured surface by scuffing slightly w/ sandpaper and it quickly became dull, so I thought not permanent enough for the dash. It works best on surfaces that won't be touched, like making a mirror on the rear of acrylic sheet.

I ended up taking them to Sacramento Chrome who did all ~6 pieces for ~$110. They use some type of multi-component spray process as mentioned by others. He said he tried several systems, before settling on his current one and said it is more durable than the factory coating. Some of the previous systems brought a lot of customer returns.