While reading Don Garlington's Imputation or Union with Christ? A Rejoinder to John Piper, I found the following in footnote 2:

"Christ became what we are, in order that we might become what he is... Paul does not specify by what modality Christ was 'made sin' though he is explicit that we have 'become' the righteousness of God because of union with Christ. But perhaps unwittingly Gundry has provided a clue. He informs us that the verb kathistemi, in Romans 5:19, means to 'establish' by way of appointment, ordination, or making... Thus, it is through Adam's disobedience that human beings 'were counted' sinful, whereas through Christ's obedience they are 'counted as righteous'... It may be, then, that there is an implicit Adam christology lurking behind 2 Corinthians 5:21. That is to say, on the cross Christ was looked upon and treated as the first Adam in his apostasy. That he endured death in a representative capacity is the least we can say... But his representation and substitution take on a specifically Adamic character as he assumes the role of his predecessor and bears the curse placed on the first man when he fell away from the living God."

Now, I have known and been aware of the things that Christ did that Adam did not. Jesus crushed the head of the serpent to save his bride, whereas Adam, all the while looking on, did nothing to the serpent and let his bride "die." The side imagery, the garden imagery, and the angels guarding are all similarities as well. But the things that I hadn't considered where those acts that Adam didn't have done to him that Jesus did have done to him. It would seem that Adam's punishment should have been to be hung on the Tree of the Knowledge of Good and Evil, which was the tree that would bring death. Adam was spared this though by God providing a substitute for him. Jesus, though, was hung, as the Second Adam, on a tree of death and of all things it becomes the Tree of Life. Death has been swallowed up in victory (life?); what was mortal (subject to death) has been swallowed up in life. The exchange and transformation is almost too mind-boggling to believe!