Get Color Sidebar Icons Back in Mac OS finder Window
Use mySIMBL* instead, SIMBL has been non-functional since apple implemented System Integrity Protection. Once you've set up mySIMBL install the package at:

Sources >>> Wolf's tweaks >>> colorfulSidebar9.

Then restart Finder and you should have colored sidebar icons again.

* I am the developer of mySIMBL and colorfulSidebar9