20 pin OBD port should be next to driver side shock tower under the hood.

I thought someone told me that its only on the pre-facelift 3.0 though not the 4.4. Maybe they were mistaken.

Or maybe it was non-sport models that had them?

Well, here's a pic form a 4.4. At the top of the pic, there are 4 black caps. Its the left most cap, nearest the windshield.