This may be a very basic question, but I've never done a complete tear out of a bathroom, and it has me thinking. Right now, I'm down to the studs and plywood subfloor. The plumbing is done aside from the tub drain and valve installation. The plumber is waiting for me to get the tub in. After I drywall, I plan to put down 1/4" CBU and tile. It seems to me that the tub should be installed after the CBU so that the floor isn't built up too high, but that would mean the proper order is: drywall - CBU on floor - tub - CBU on walls. Is this correct? If not, what is the proper order?