Adding LTM to GTM with different version

Hi Experts, I am looking for a KB that shows the prerequisites or consideration prior doing BIGIP ADD in GTM. Are goal is to use GSLB functionality of our GTM. Our GTM is running in 11.6.1 version and we will upgrade our LTM from 11.6.1 to 13.0. May we know if it is possible or there is an issue with this setup.