I would remove the coolant, but that's all. You don't need to remove the excess tank, although if you need to, you can remove the two small hoses to get them out of the way if they are. Also remove any gunk around where the gasket goes just to make sure it seals properly.
I went to an Autozone and the guy there was very helpful as to anything else I might need. So I would ask, although I guess since really anyone can work there, I wouldn't take them to seriously.
