This weekend replaced the Suburban hot water heater for an Atwood 50K BTU on demand hot water system. Not the easiest task, but it came out really well. As the Atwood front cover is way too large for the area, the original cover was modified and used. Actually the hardest part was getting the gas line disconnected from the Suburban as there was at least a hole tube of the black caulk behind the area where the fitting came through the side. Once the old unit was out I added a flexible gas line removed the 110VAC line and prepped the base by removing the two 2 x 2's added a small block as the platform was not square to the front. There is plenty of clearance around the unit for water lines etc. I removed the bypass lines as with an on-demand unit they are not required. Purchased new water lines and Shark-Bite fittings from HD. Bent them into the plastic corners using hot water. Had to remove the front flanges from the Atwood which was easy as the were shipped bend over and only attached by little tabs. So just wiggling back and forth a few times and off they came. Had to make and add little tabs to attach the front cover to with Rivets. Sealed the unit from the coach using Alum Tape and sealant. After the install the system started and worked perfect. Some have complained about the flow rate needed to turn the unit on, but I found this not to be a problem. Attached are some pictures.