Hi agashamirv - the primary forum for CWC has now moved across the the Pendraken forum - as they now own the rules set. You'll get a lot more answers there - but old stalwarts like Bilb & I remain on-watch over here
Converting Team Yankee to CWC is pretty easy - the thing to do is hunt down some of the original NATO (& US) and Warsaw Pact OOBs that are now becoming available on line.
These usually tell you pretty much what vehicles are in the command formations. In 6mm I use a variety of vehicles on a command base - so my US Army tank formations might have an MBT (Abrhams) + an ARC or a medical vehicle for a MBT formation. But in 15mm you'll probably not base stuff up in that way (but for command it might be worth it).
My 82nd airborne has a grounded command chopper (for example) with a few 6mm figures out on the ground looking at maps, with a jeep nearby. You can actually be quite creative.
As most command bases also have AA stats in CWC, a Stinger squad makes an appropriate addition on the base alongside the command Abrhams.
Welcome onboard