sometimes you get an answer ,but more often ...

you'll get more questions than answers about these one off sk/xe part numbers ! we're no experts here .
What you have is a later development than any of the 427 heads we have listed thus far .

Tell us what you can about these heads , specifically how they differ from other tunnel port heads (as far as you can tell) sometimes their is only ONE REMAINING EXAMPLE of an sk/ask/xe part and no existing records in anybodies collection of ford logbooks that pertain too the parts themselves .

So tell us what you can and we'll go from there ! Sadly we may not go very far....