Just thinking aloud here...if we trade Henry for Shelton, and release Pierson, then the cap hit is essentially a wash. Shelton I believe is a 3 million dollar hit and Henry + Pierson = 3 million dollars as well.
So now our O-Line would be Shelton, ?, Teague, Villarial, Williams.
Not bad. We can then use the extra 3 million we got (putting away 3 million for the Draft) to sign a quality LG like Vincent and a backup QB.
Then our O-Line looks like Shelton, Vincent, Teague, Villarial, Williams. Even better, and we still have money to sign our draft picks. In the draft we can nab a backup RB, a WR to compete for the 3rd WR spot and some more O-Line depth. I'd be content with that.