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This vehicle does not use an egr valve. A place is there for an egr valve in case it was needed for emissions reasons in other vehicles but yours should have a block off plate in the location shown below.
The heads should be the same. As far as a GM part, there should be only one part number. The only difference would be on a different vehicle that uses the same engine and requires an egr valve, it would have one. On yours you would swap the block off plate onto the new head.