Via the exterior
Open the outside water heater access panel and you will see all the screws in frame that have to be removed, cut the sealant between frame/exterior of RV, disconnect the gas line
From inside you will need to access backside of water heater to disconnect AC/DC wiring & water lines
*May be able to do so from outside if enough slat in wiring/plumbing
WHAT do you plan on replacing it with?
Cut out is sized for that water heater....others will require different size openings!
WHY are you wanting to replace that water heater??????
What is the BRAND/MODEL????
Is it time for YOUR Medication or Mine?
Dodge 3500 w/Tractor Motor & NUWA 5vr
US NAVY---USS Decatur DDG-31