1. Yes-there won't be any sticky residue mess (hopefully)
2. Extra rings are so you can change at another time, should you need to replace the adhesive.
3. Line up the seam of the pad with the hole in the ear cup. Just the "hole" side (faces front), not the hole with the slot side (faces the rear). Have a look at them before you take the LCD 2 pads off.
You will be fine.