[Q] updating an existing rooted moto g (xt1032) from kit kat to lollipop topic

Could somebody post a link or explain how to update an already rooted xt1032 to lollipop from kit kat. I found every other type of method but only if its running stock. Every way I enter a search for this its always dealing with stock firmware, is their a guide for the rest of us?? Thank you and p.s. its a first gen moto g, thank you again