I recently read in Airways that El Al is considering converting their PAX 744 into 744F in the long run. When converting a PAX 744 into a 744F, is the upper deck modified to the original size upper deck or is it left as it is and only the seats and galley equipments are removed? I know that a 747-400F fresh out of the factory is built with the upper deck of a 747-100/200 to save weight, but I think that on the other hand a 747-400F that was originally built in PAX version has its upper deck remained as it was. Does that mean there will be 747-400F's in service with strech and non-strech upper decks? It will be the same for the new 747-8.