No need to buy the shanks, the 545PCs will fit right into the shanks the tower comes with, that's exactly what I've got. Unless you want to upgrade the chrome shanks to SS, but firstly you'll have chrome taps so why bother with SS shanks, and secondly it'll be such a PITA to replace the shanks that I wouldn't bother (in fact I considered the same option but dismissed it once I looked into the tower and saw those shank locking nuts all so very close to each other).
EDIT: Screwy, you're good to go, no looking back once you have the flow controls.