Grounding the engine. Two grounds are run to the engine for redundancy, one for each battery, but there's a wire that connects the two at the engine, just like there's a wire to connect the two grounds at the batteries. I added 8mm grounding studs to the grounding points under the engine. I also added and connected a grounding buss to the root tube, for convenience of grounding certain other engine and wing light electronics. After the wires are in place, I'll bundle them and strain relieve.
Grounding buss added under engine, with 10awg wire to engine ground
