1. I'm wanting to install a new gas water heater. I was planning (for simplicity) to add stainless steel flex water and gas lines from the existing lines to the new water heater. Can I do this? 2. I need to add a shut off on the cold water supply. I was thinking of a 1/4 turn ball valve that would connect the copper line to the ss flex line. Do I need a dielectric fitting in between that? 3. Other things I am missing or may need.