The factory used whatever engines Ford shipped over in bulk, in whatever order they appeared on the line. No exact cut-off dates for anything on/in these cars is known for sure. The Cobra-Jet engines were introduced for upcoming smog law reasons in the U.S in late '72, with open combustion chambers, lowered compression and retarded cam timing compared to 1971. One thing is for sure: no production Pantera imported by Ford ever got an OEM Boss-351 nor a 351-HO (both with solid lifter cams), simply because they cost more. Ford was cheap-skating everywhere during production and DeTomaso was worse. Euro- Pantera buyers could select higher power engines in the Gr-3s as an extra cost option and of course the racers had unknown spec but likely high horse motors, but since there were less than 40 GR-3s & only 14 GR-4/GT-4s ever factory- produced, they obviously were rare. For private engine swaps, who knows?
As for Campys, there were one, two and three-slot Campagnolo 7" & 8" x 15"s used in production, also in no particular order, although '71s seemed to have gotten most of the single slots. When we got our Sept '72 in mid-1980, I was told single slot wheels had a reputation for cracking. I've never seen a running example with three-slot wheels so I suspect they're the rarest. Our 7-yr old car with 23,000 miles & three owners had four hot-rod style 8" x 15" aluminum wheels- no explanation.
A few Panteras had their magnesium wheels removed by Bill Stroppe right off the ship and various CA aluminum wheels substituted at dealer requests- much to Ford's dismay as they were dealing with daily DOT and smog law changes & didn't want extra Federal attention! Two cars with consecutive serial numbers might have gotten different factory slotted type wheels depending on what Luigi pulled off the shelf. The vast majority of OEM Campy wheels were two-slot both in the US and in Europe. But a lot of switching around can occur in 50 long years with multiple owners in multiple countries & short memories.... Bottom line- no one knows for sure on either question. POCA has 300+ pgs of archival Ford memos & panic-faxes on their web site from this period and it was utter manufacturing chaos & daily running mfgr changes for 3 solid years! After Ford bailed in mid '74 on DeTomaso, they showed they were slow learners: Ford tried to buy Alfa Romeo in 1975 but local boys FIAT outbid them.