KINGSTON KITCHEN BATH Before starting the installation: Straight supply lines are designed to ba installed on tubs that are configured for deck mount faucets, and should be installed at the same center to center distance as that of the tub faucet holes, the supply lines should be installed in a plumb vertical position before starting the installation we recommend: © That you have the supply lines and faucet at the job site prior to preparing the rough-in water: "Suppl.