Well well well, i see another confusing 7th gen owner about the face-lift conversion, when i restored my 01 7th gen i thought the same and decided to go for a face-lift but fortunately i found a complete RS Conversion of the pre-facelift so dropped the plan. As for the resale purpose it wont effect cuz car is already getting painted in the near future so its just a facelift, just keep in mind not to paint the nose and bay which may effect the resale value.
You need the face-lift Hood, Both Fenders, Headlights, Bumper and Fog Lights for the complete face-lift conversion which will cost you around 30-40k depends on the condition of the parts you choose from the junkyard apart from the bargaining, i would recommend you to exchange your current pre-facelift parts with the face-lift ones, they won't take it for a good amount but still it will create some negotiation. And yes, pls do post the pictures of your 7th gen!