Reverting back to 4.4.2 stock?

I'm planning on returning my Verizon LG G2 VS980 back to exchange for the ATT variant. Sorry if this question is obvious but I was wondering how to revert back to stock, like on 4.4.2 with LG's original os. As of now I'm on 5.1.1 Blisspop and should I use KDZ Method or the TOT Method? Is it even safe to try reverting back? or did I screw up by installing lollipop. Sorry I'm only used to using Samsung phones and using odin to bring them back to stock.