A380 operational cost estimates seldom mention the cost of improvements in infrastructure necessary for the care, feeding and operation of the new Airbus. These are far in exceedence of what would be necessary for Boeing. Remember that even in the cargo configuration you still will have to deal with double decker cargo handling systems. I do not know how much of an impact this would be.

IMHO I am thinking that the capital improvements that would be necessary for the Airbus will probably far exceed what was necessary for the implementation of the 747 into the 1969-70 air transportation system.