Poor A$$ Stock '93 said:
The only reason that I haven't seriously considered a supra swap is water. I play in mud and water a lot and would be worried about nuking the turbo with a blast of ice cold water during a creek crossing. Is this actually much of an issue? Also, on the trail, my engine rarely spins the rpms it takes to spool up that power.
Which means your turbo will never get hot. Without spooling the turbo, you turbo shouldn't get any hotter than the eghaust manifold. So, unless you are worried about the manifold cracking, I wouldn't worry about the turbo.
The only time you should worry about the turbo, is if you are hauling butt up a steep hill for a long time, then decided to take a dip in an ice cold lake. Just make sure if you were hard on it, prior to river crossing, to let it cool down for a few minutes.
How many diesel turbo's are there out there that do deep water crossing. Lots, especially down in OZ. They don't ever worry about it.