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You forgot to mention a L67 info.No EGR and alloy fuel rails is from VS
EGR and steel fuel rail VT-VY, then you need to look at the intake PCV port location inside the plenum. If the PCV hole is located in front of the TB than it's the later ecotec, if the PCV valve is next to the intake runner then I believe it's from the VT's.
TrueWell he did say ecotec.