How difficult is it to manually replace an Early 2015 Macbook Pro's battery? I have a MacBook Pro (Retina, 13-inch, Early 2015). My battery health has deteriorated, and I may replace the battery some time this year. A full charge still gets me about 3-4 hours of use time, and I keep it plugged in most days, so getting a new battery is not an urgent need at the moment. 

I think Apple told me that it would cost about $200 for them to replace the battery (battery + labor fee). If I do it myself, I think I can do it for under $100. How difficult is it to change the battery manually assuming no prior experience? Also, how easy is it to screw something up during the process that will make the macbook permanently unusable?
So it can be done, but the battery is glued in. ifixit do sell a kit to remove this, but it is still a bit tricky. 

Be very careful not to puncture the battery!