Scott,
Here is an interesting site extolling the benefits of electric power
steering pumps:
http://www.automotivedesignline.com/howto/165600237

They claim:" the hydraulic steering system in your car siphons off
somewhere between one to three miles per gallon from your vehicle's
performance and consumes more energy than your car's air conditioner? In
fact, it's the third highest energy-loss mechanism in your car, following
wind resistance and road friction."

Three extra miles per gallon in a Vanagon would be significant.

Ken Lewis