Order of operation is everything when it comes to plumbing 👍 And even then when it comes to installing a new bath tub, you'll need to dry fit it multiple times Here's a game plan to the installation of a new tub: 1. Check subfloor for levelness (Anything with in 1/4" over 4ft is usually okay) 2. Dry fit tub, check levelness, & mark wall studs at tub flange 3. Measure tub flange thickness (every tub is a bit different) 4. Deduct that thickness from markings on studs 5. Set ledger board at that l