This submod is very straightforward and similar to my MOS submod that adds beautiful barded horses for Gondor cavalry units. This submod only changes a few files in order to change the mount type of one unit, the "Gondor Bodyguard" unit (i.e. your generals' cavalry unit, minus Boromir and Faramir). Just extract this .rar download directly to the main "data" folder in whatever folder you currently have your DAC submod placed in. When it asks to paste over everything, just say yes.