Early 6.0, no dummy plugs.
End plugs on oil rails are not service items. One of them had been removed and galled the surface behind the oring groove. Fortunately the threads are ok.
Friend that does these by the hundreds gave me an 06 wavy rail, end plugs are the same.
The little hex plugs are just metric boss orings. That wasn't an issue
The end plug is some kind of quad ring looking seal. And it's an odd size. Not available from Ford or IH.
Oring house had nothing.
AND, as it turns out the Ford reman Injectors with 40k in 5 years on them are complete junk.
Oil exhaust side of the spool just pours oil out on the first three injectors they tested. Picking up new injectors from them Monday morning from Allied which is a pure Power Injector