If you want to remove the waterpump, remove the radiator first.
I don't think you have to remove the waterpump to pull the head. It is attached to the block, not the head.
Do you have a shop manual? If not you might want to review the online shop manual info at the
Old Online Chevy Manuals project. Here is a link to the section of the shop manual about removing the head
Removing the head. Good luck!
Kurt
