Tuning: Drop D
Taken from Acoustic version...super simple. 
You should be able to figure out the rest and timing/strumming pattern from here

Note: minor variation of other "So Long" tab 





intro/verse - can play around with this picking as you wish
e------------------------------------------------------------------|
b-------3----------3-----------3-----------------------------------|
g---2----2-2----2---2-2-----0---0-0---0-----0----------------------|
d--0-0----0----0-0---0-----2-2---2---2-2---0-0---------------------|
a-------------1-----------3---------3------------------------------|
d-0---------------------------------------3------------------------|
                                          


chorus
e--0-----------------------------0---------------------------------|
b--3-----------------------------3---------------------------------|
g--2-----------------------------2---------------------------------|
d--0------8-------10----8-7------0-----8----7----10----------------| x 2
a--0------8-------10----8-7------0-----8----7----10----------------|
d-0-------8-------10----8-7----0-------8----7----10----------------|