Basically you must be rooted before doing this.
Download above file posted by chevy
Use a file explorer program like root explorer browse to your download folder or wherever you downloaded the above file. Extract it and when it says go to extracted folder say take me there.
Once there click on the vold.fstab and long press it and select copy from the menu that pops up.
Then browse to the root of your system device and select the system folder
Once there select the etc folder
Once in there at the top right of the screen if your using root explorer change the r/o to r/w and paste the file in here.
It will ask you to overnight the file. Select yes to overright
Then at the top right of your screen change the r/w to r/o
Finally reboot your phone and you should be good to go.
To verify just go to settings and select sd card and storage and you should see your external sd card showing up as the main sd card now.
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