First, you've got to get the surface super smooth, 100%! Even the smallest flaw will show up big time once it gets chromed. And if you have to fill any holes or other imperfections, you have to use something tough like Bondo. Most other "fillers" can't stand up to the chroming process.
I looked into this a few years back, and after talking to the owner of a chroming shop in Cali, I came to the conclusion that it wasn't worth the money. You could go through all the prep work and pay to get it chromed, only to end up with something really ugly.
Now AlClad, there's something I'd try. From what I've seen you get almost the same effect at a fraction of the price. And if you mess it up, you can strip it down and start over.