I've had two different sets of heads on my 3.4.
None of mine have ever lined up, exactly.
Just put a dab of silicone at the place where they join, just before you put the valve covers on.
This has never caused me a problem with either oil or coolant leaks..
88 4.9 Formula IMSA Fasback..........................88 3.4 coupe -soon to be something other than red
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