In regards of the aurora engine i think one or few of the transmission's housing bolts would need a slight relocation mod in order to fit properly.
Here are both,the VX & the 2005-2011 MDX engine-drivetrain specs
Vehicross : V6 3.5L DOHC 215hp @ 5,400rpm torque 230ft-lbs @ 3,000rpm
2011 MDX : V6 3.7L SOHC 300hp @ 6,300rpm torque 270ft-lbs @ 4,500rpm 2005 MDX : V6 3.5L SOHC 265hp @ 5,800rpm torque 253ft-lbs @ 3,500rpm
As you can see the 2005 acura seems to be better suit for our VX then the 2011 in regards of power