You do not say what version of MEP you have and the options differ slightly between them.
In MEP14 and earlier there is a little box with 2 upside down V's, at the far bottom right of the preview monitor window which will toggle the Jog wheel and slider on and off in normal or fullscreen mode.
In MEP16/17 there is an option to only show the picture itself in Fullscreen mode by right clicking in the picture and selecting "show (hide) transport control". This is only available in Fullscreen though and all the controls disappear.