I used the "top down" method and, after I figured what the best way to pop the tabs off, it went fairly easy - and, with a long sleeve tshirt and gloves, no scratches on my arms or hands.
A member or 2 here said that there tabs appeared to be "melted on", and based from the pics they posted, it looked like some of mine were as well, but that wasn't the case with me and the tabs popped loose.
From the top, I used a screwdriver as a lever to pop off the top tabs of the center section. Then I used one of my interior removal tools to slide in between the remaining grill tabs and the grill openings from the front and the rest popped off easily. Once the front section was out, I had easier access to the sides and used the same procedure.
Installing the new grills wasn't bad either, just had to get the top & bottom locator guides of each piece in place and, reaching through the grill openings, press the tabs in from the rear, holding the grill from the outside. Did the other side the same way. The center section was last, and since there is no longer a way to reach through the openings, you have to reach down from the top.
Do not fear the "top down" method