The way I see it, it would have to start with Bynum to Cle AND Gasol to Houston. The Lakers take back Howard, Turk, and Glenn Davis from Orl (I think that part works as salaries match for the Lakers and Cle and Hou are under the cap).
Then to make it work for Orlando, they get Varajao, a young player, and a pick from Cle and they get a pick and a young player from Houston.
Cle likes it, they get Bynum. Houston is happy as in the past they have wanted Gasol. And this is not a bad take for Orlando.
Under this scenario, it is the Lakers who should hesitate. They get Howard for Bynum, OK, say they view that as an upgrade, but then they "dump" Gasol and get back Turk and Davis. I am just not sure the Lakers are any better. If they really want Dwight though, I think this is what they would have to do.