15 minuten - 1 uur
Phone would die instantly without being plugged in. Noticed the battery getting weaker and weaker after a year. Eventually the phone bowed out, almost bending the screen out because the battery had exploded and was expanding.
Took a good ten minutes. Had the wife hold the phone screen once it was open and didn't mess with any of the ribbon cables. I wouldn't take out the ribbon cables, just hold the phone up to 45 degrees opening from the bottom. The most difficult part was getting the battery out since it is glued and you can easily break the phone if you apply pressure on the chips.
I recommend pulling out the battery by using the ribbon cable connected to the old battery and holding the outside base of the phone with you fingers. DON'T USE ANY TOOLS when taking out the battery, you can pull it out using the ribbon cable and holding the frame with your hand. You will most likely ruin the old battery and ripping the ribbon cable, which I did, but my battery was already exploded so it didn't really matter.