I even removed the water tank (water pump housing cracked and leaked water
on floor of van for months before I realised it) and now used the extra
space to store emergency parts & tools like an extra water pump, inner tube,
coolant hoses, gas filter, alternetor brushes, coolant expansion tank, etc..
 The electrical connection I only used at most three times in twenty two
years of ownership so I removed even the wire and use the extra space for
storage which is always in demand on long camping trips (all provinces in
Canada and every state in the USA except Hawaii & Alaska !). For the small
amount of dish-washing I do, I carry a one-gallon bottle of tap water if no
taps are provided in the camp ground. I even removed the fridge (not great
in my books anyway) and now carry a small $20.00 cooler that fits in the
same compartment along with other things.  My two cents worth anyway!

Sam