Well, that 'little tweak' will involve replacing the original guidance module with multimode radar, IR, GPS/INS, and probably also laser homing guidance system - the latter will be especially useful for precision strike against ground targets. Then the control surfaces and the rocket motor gimbal/steering fins will also need to be modified accordingly so that the missile will be able to adjust its trajectory continuously during its terminal phase to make sure that it will hit a maneuvering frigate-sized target.Well maybe with little tweak and then shoot the missile to the general area, then using radar to lock ship in there and/or with two way datalink comm for visual confirmation/targeting.
If it able to lock at the target then even if the ship is moving it still can be hit.
Also, since this kind of missile is much easier to spot by enemy radar at a much longer distance than a sea-skimming one, we can either:
a. fire a volley of multiple missiles against a modern enemy surface combatant or naval task force,
b. implement RCS reduction measures to the missile,
c. make it able to perform some kind of evasive maneuver to defeat enemy's sea-borne ABM, or,
d. all of the above.
So yeah, I'm not holding my breath for this to become reality - it's just a wishful thinking at least for the time being since we don't have most of what it will take to modify the missile to such extent.