Are these filters still located on the right hand side for right hand drive cars?
If yes, then I presume a different procedure may be required due to the presence of the steering column?
If no, then is the method the same but reversed?

This video was from a W164 model. Is it essentially the same for W166?

 

Not the same for W166

I recently replaced both filters in my newly acquired 2012 ML350, and did them both from the engine compartment. Just pop the access for the plain paper filter, remove it, and then you can see both carbon filters. This did require squishing the carbon filters a bit while installing them, but they are flexible and there appears to be no bad effects from said squishing.

Doing it the first time took about 5 minutes of actual filter changing time, once I take out the time due to hesitation and waffling

Edit: should mention this is a NA left-hand drive vehicle.

 

I just did my engine & cabin filters. As was mentioned, when you remove the cabin dust filter, you can see the 2 combination filters behind the glove box. I was able to reach in & take the old ones out. However, I could only get one of the new ones in, didn't want to keep squishing the second one too much so I went onto removing the glove box. PLEASE NOTE, the above video is for a w164. Our w166 has a little more to it, not even mentioned in the MB service docs that I found. You have 3-T20 torx screws holding the panel in the passenger foot well. Pull this down too much & you'll disconnect the vent attached to it. Inside that vent is some kind of temperature or humidity sensor. GL lining that back up if you do accidentially disconnect it. Not mentioned is that above those, on the side towards the middle of the car is also another T30 torx that comes off. Open the glove box to find the 3-T20 torx along the upper edge. Pull off the side panel & you'll see one T20 and one T30. The video mentions disconnecting the wiring for the light & letting the glovebox rest against the center console but in the w166 on the top left is a vent tube that supplies the cooling for the glovebox that will pop out from it's supply a bit above where that T30 screw was. Also on the right is another wiring harness attached to the glovebox's dampner/shock. I left that attached & rested the glovebox against that right side. I took pics of when I did the air filters but not when I did the cabin filters, just gotta figure out how to do a write up. There's lil gotchas w/ the air filters as well Took about 1.5hrs total.

 

Much simpler to just remove from engine bay..remove top cover...remove inner funnel..pull out outter filter..pull out inner filters..replace all...done..5 mintues

 

If you can get it in from the engine bay, by all means do so. The 2 combination filters are sitting right there when you remove the dust filter. I ended up removing the glovebox because I gave up trying to get the ones in properly.