I used copper also and helped several in our rally group repair the water lines using copper. Be aware that if the leakage has existed for some time before complete failure, you may need to rebuild the rotted plywood floor of the fridge compartment.
I also reused the heater wires wrapped around the copper pipe and retained the heating function. Since we rarely are in a freezing situation, I have removed the fuse for the heater.
If no wood reconstruction is needed, just sliding the unit partway out into the hallway was sufficient for me to get to the back side to do the repair work.
2003 34' Dolphin 5342, W22, UP, UPGBrake, F and R Track Bars, Rear IPD sway bar, Koni FSDs, Safe-T-Plus, Scan Gauge II.. 2004 Jeep Liberty, Blue-Ox Adventa..