I'm not sure what was stock on the 2007 and older 4.7L. I know on the newer 08+ but it's not the same. The new engine uses 2 plugs per cylinder, both different, and the old engine has 1 plug per cylinder. I'd assume it's not the same as either from the newer engine.
Should be in the manual or something...
I am almost positive they also have 2 per cylinder like my hemi does, and they are both same plug(2003, 3rd gen). His plugs will just be 6987 ngk
EDIT: Sean you seem to be correct and only one plug per cylinder. I just assumed it was the same as the hemi. I checked out this video