4.6 Heads & Valve Covers

[DonNicholas]

I am new to these motors - some help would be appreciated.

I have 2 versions of 4.6 motors: a 94 (supposedly PI, but not really sure as I know it was swapped out at one time) and a 2000 Mustang with PI Heads.
When I bought the Mustang I thought that they normally came with the PI heads (Know they are PI because of the casting ID). Now it turns out that maybe they are not normal. (PI = Police Interceptor)
I have been trying to obtain a new valve cover for the one with a broken oil fill tube without success. The set I bought recently was suppose to fit Mustang GT 96-2001, but they appear to be more like the earlier type (i.e. 94).

What I have is 2 different bolt patterns on the covers: the earlier one has 11 in all; 5 along the top and 6 along the bottom all pretty much in a straight line. 2 are in front of the cam gear hump. Kind of like the diagram below.
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The newer one has 14 in all; 6 along the top, 6 along the bottom, and 2 in front of the cam gear hump. The front 2 are displaced toward the center-line of the head from the rest. And the rear-most one on the top is offset from the line further up a little. Kind of like the diagram below.

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Does anyone out there know whether the newer one is completely unique to the PI heads or is it common to the Mustang GT 4.6 or something else entirely?