If you have the Y enabled then you should be able to move it. The hotkeys for jogging will be different, in fact they are probably not set up in lathe mode (never looked) but if you go to Config menu then System Hotkeys you could set up the keys you want for Y. I would think that PgUp/PgDn might be best to use as it will likely be they are not used for any other HotKey, but be careful whichever you choose just in case they are already assigned to another function.
If you are needing the DRO for the Y then you will have to add that to a screenset yourself with either Screen4 or MachScreen.
Hood