I am removing all of my yucky mercury silver fillings and replacing them with pretty white composites. I have already done 6, just 3 more to go!

I have an old porcelin crown with this silver rim on the bottom. Since I have already gone to so much trouble to remove the silver fillings, shouldn't I get a new crown too, or am I a nut? I am assuming this is the same stuff that my silver fillings were made of, right?
I also have one gold one that I was just going to leave alone. Is that a good idea, or should I just switch that to white too? It's pretty big, so he would probably have to crown that too.
Any opinions?