having done the 4bt cummins swap, and being in the process of another i reckon the 4bt in a patrol would only be ok. gearing it high enough would be a drama and the cunt is 3 feet tall ! a 6bt is too fucken heavy. the b series cummins motors seem an awesome thing though.
from what i can gather gm designed them to make mounts and shit all the same, so anywhere a sbc will go so will a duramax. aren't they all aloy too ? i spoke to a bloke at powercruise with one in a patrol and he reckoned it was easy to fit and awesome.
the 6.2/6.5 things brunswick diesel sells are overpriced pos from what i can gather.