Shipping C&R guns OUT of California only requires you present the shipper with a copy of the receiver's C&R license (You can't get a verification from the ATF QuikCheck (Sp???) website like you can for a regular FFL because that would disclose the collector's home address, a bad thing).
Shipping a C&R gun into CA to a C&R collector's license has some CA legislative wrinkles that are explained (I think) on various forums on
www.calguns.netNot having a C&R license, I just treat C&R guns like regular guns when I have them shipped to me in CA--FFL to CA FFL if they are "allowed" handguns, FFL or individual to CA FFL if long guns. If you do the latter, make sure the FFL you are shipping to will accept guns from an individual and include a DL copy to show you aren't a minor.
And buy stock in a paper manufacturer!