How to get the nexus firmware on the s5?

No offense to Samsung, but I kinda hate the touchwiz and all the other clunky components of the s5 running lollipop. Unfortunately I didn't know this when I bought my s5 for 0 or I would have gotten a nexus instead. I've been told by a friend that it's possible to get the firmware used on the nexus 6 (the original lollipop) on my s5 if I root. I'm not afraid of rooting, but I can't seem to find anything about getting the unaltered lollipop on my s5. I don't know if this is even possible, but material design is the reason for my existence at the moment and my s5 running lollipop doesn't have enough of it. Thanks in advance if anyone replies.
(btw, searching for "stock lollipop on s5" in google only gives me the samsung-altered firmware for the s5, so I was hoping someone here could help)
:)