Originally posted by gearhead98:
ok the numbers off the right head are
RF-IS7E-6090-DC
not sure if that is a 1 or I tho

Numbers off the left head are
RF-IS7E-6C064-AE

Those are 2001+ model year 2.5L heads. The 1S7E prefix on the part number is the clue. For 2001 model year, there was some commonization done between the 2.5L and 3.0L block. The 3.0L block had some extra mounting points, etc. for the Jag/Lincoln LS applications. I think those were now also needed for the 2.0L/2.5L Jag X-Type.

One result was that the 2.5L block got an extra set of drainbacks that the 3.0L has always had. The head was changed to match.