There are likely a lot of good spots to mount the FOG, and its not an expensive item, so why not mount one. I asked this question early on, but waited until my electrical, instrumentation, and engine monitoring firmed up. During designing my system and choosing the components, I kept an eye on the Fwf grounding requirements. Well, my dual Dynon Skyview with Ems is fully installed and operating, ie, all electrical is complete. Not a single Fwf ground other than the common point on the firewall for the battery and engine ground anchored with a bolt. My assumption is that a lot of the need for Fwf grounding may be pre-glass panel/ EMS. I do have a large FOG behind the panel with probably a dozen tabs used, but none Fwd.