Don't take out your cross bracing...unless you want a busted tank... I just don't see it ending well without the bracing. If you paid that much for driftwood I'm assuming its malaysian which is dense enough that it sinks without having to be water logged. Moving big malaysian wood is a pain if you haven't tried to yet, I've got 2 large pieces 2ftx18" roughly each and they are about 40-50lbs each. The stain that the driftwood puts in your water is good for the fish usually and adds some natural minerals back in, its harmless otherwise discounting the yellowish brown color but the carbon in your filter takes that out in a couple days. Malaysian driftwood also lowers your pH, with those 2 big pieces in my tank it dropped about .3 ~Trent