Smoking crack they are... As far as accuracy :rolleyes5:
Diesel Power (6.6) is not Diesel Economy (6.5). You can get both out of the 6.6L so the swap wasn't in tune with the magazine subscribers.
The AC Compressor was located on both sides of the 6.5; driver's side being a later improvement for vibration and bearing life due to less load on other parts from compressor location being a shorter belt load path to the crank. True, most other GM truck has a separate AC belt located on passenger side. But the gassers of the era had the same changes from passenger side to driver side AC location. Downside being longer AC hoses and that may be the reason GM put them on the passenger side since AC was added to cars way back when.
So their quote is a "So what?":
"While no one would ever confuse the Duramax for the 6.5L, you can certainly see the family resemblance between the two. The cylinder bore (4.06-inch) is the same, the oil filler tube is in the same location, the A/C compressor and power-steering pump are still on the driver side of the engine :dr: , and even the engine's main electrical connectors are carried over from the 6.5L."