GustavoFerri,
Refer to this whitepaper for deploying/upgrading OMSA on all the targets using OME.
en.community.dell.com/.../20069180.aspx
Since 60 servers need OMSA upgrade, I would create 3 separate OMSA deploy tasks in OME. Each task will upgrade 20 servers at a time and run these tasks sequentially.
Thanks,
Raj Shresta