Regarding water heater:
Drain, Plug hole, Blow, Drain, Plug hole, blow, Drain again, plug hole and do around 10 more blows, each a few minutes apart (This gets most all the water out) then drain and plug again, If atwood remove red wire from ECO and you are good.
Pump
Leave inlet valves (if any) open, and drain plug out of tank or valve open.
After first blow access pump , take a towel with you, lay towel under pump inlet strainer. Open the inlet strainer and let it drain into the towel (Less than 1/2 cup) turn on pump for like one minute, Turn off pump, re-assemble inlet strainer (This is a turn latch, make sure it is firmly latched)
That will do it.