It has been my experience with 5.4 engines that they use a qt of oil in about 2500 miles until one I owned had about 80,000 miles on it. The other one used a qt in about 2500 miles until about 70,000 miles. After that many miles the oil consumption was a qt in about 5,000 - 6.000 miles. It takes a long time for the rings to fully seat.
I've had a similar experience with a 94 5.0 truck engine and a 200 cu. inch 81 Granada engine.
Also, full on my truck is at the 1/2 qt low level on the dip stick. If I add that extra 1/2 qt, it will disappear until it gets to the 1/2 qt low level.