IF I had to move Havenstein for cap purposes the only player I'm comfortable replacing him with from this roster is Edwards. Edwards has shown from day one that he's got NFL strength and hands. He's the guy. He'd need to adjust his feet to RT which is a complication but he played RT at Wisconsin and it wouldn't take him long to settle in. I would guess he's not as potent as Hav in moving guys in the run game, but he'd probably be a passing game improvement.
From there you need a LG. Does Anchrum come into consideration there? Moving Hav would suck. But it would allow them to move money from RT to C. And we'd be looking at something like...
Whit // xxx // FA // Corbs // Edwards
LG could end up being Anchrum or a rookie which is fine at guard. FA could be one of many possibilities. Is that OL overall better than what we have? Maybe so.
Oh and imagine if the rookie is Meinerz mauling MFers and the Center is a second tier guy like Reiter. You probably have yourself a top tier OL.