Return rooted VZW xt1060 4.4 back to stock

Hi,

I rooted my GF's Verizon Moto X on 4.4 like 2 years ago and can't remember how I did it. I feel like it had something to do w/ slapMyMoto or one of those toolkits.

With the announcement of Lollipop finally being released I wanted to return it to stock so It can be updated to 5.1.

Does anyone know how I should go about doing this? Is it as simple as just doing a standard update? through the software update in "about phone" or will that break it without reverting somethign first?

EDIT: when i click on update, it give me the following error "Unfortuantely, com.motorola.vzw.settings.extensions has stopped"

THanks and sorry for the probably dumb question. I've been too spoiled w/ nexus'.