If you're looking for a player to drop so that we can make the switch, it's Mario Williams.
While it woudn't be the greatest bunch in the league, we already have 4 solid LB's. Move Spikes inside with Fletcher and let Crowell and Posey (who played pretty well in Houston's 3-4) have the outsides.
Mario Williams and Schoebel would be able to handle the ends.
This still leaves DT, but IF Washington could be brought back in, he and Sam would be okay controlling the NT spot.
I believe with that line-up, and Cotrell running the D, we could successfully make the switch this year.
How possible is it? I think the Washington thing could happen, but no way Mario drops to 8. We would have to trade up to take him, and it just wouldn't be worth it. Not with all the help the O-line needs.
BTW...I LOVE the 3-4! I would love to see this happen if it were possible.