Over on dronetrest Karl posted a great guide on how you can connect the ProDVR module to the EV800 goggles to record your FPV video feed. If you are comfortable using a soldering iron, its relatively simple as Karl provided the locations where you need to solder the DVR unit.
Read the guide over on dronetrest – http://www.dronetrest.com/t/eachine-ev800-mod-with-eachine-prodvr/2774/1