I succeeded following this guide and replacing my battery and phone is working without problems.

However there is a few things that this guide does not include, and i think is very important to mention them in this thread.

1 Be careful when you use a suction cup to lift your display from the chassi, if using to much force the display will violently pop off the chassi.

2 When removing battery, try to slide something small under the battery to release it from its glue on the chassi, i had to use alot of force to get it off, i thought about giving up because it looked so easy removing it in the guide.

As somenone suggested it maybe better to use a hairdryer or a heatgun to apply heat to the battery before removing it.

3 When you have completed all the steps and assembled it back together. Reset your network settings and connect the phone to a wifi network then the phone will get the signal back.

*TIP If you arent getting signal, check that the antenna cable is connected in the logic board!