How to change properties of an item in a legend in ArcMap 10.2 using python

For many of my projects I use a single mxd to create multiple maps using a python script to switch on/off various raster layers before exporting to pdf. Before beginning the exporting process I currently have to open the legend properties window, go to the items tab, individually double click on each raster layer (often 50+ raster grids) and untick the "Show Layer Name" checkbox for each in order to display it correctly in the legend. As this is a highly manual process I almost always accidentally miss doing this for at least one raster in the list and have to spend time working out which layers to switch on/off before manually exporting.

Is there a way to automate removing the layer name line of each raster in the legend using python? i.e. leaving just the "Heading" and "Labels" boxes ticked.