The Duramax is quite a large engine. Especially when you factor in all the plumbing required for the turbo, intercooler, etc...
Not to mention it requires a massive radiator.
These trucks already having clearance issues with the steering column, and radiator even when installing a small block. I can't imagine what a Duramax would be.
I do like the idea of a DMAX in an AD truck, I'm just not for sure how it could be done.
Maybe look into selling your drivetrain and installing a 6.0 LS. Heck, you'd probably end up money ahead.
