Don't you know he's talking about raising trees, I thought it was obvious
Trees are grounded, so there is a definite thread to it
As an aside, you'll have difficulty in grounding the panels unless you put a bolt through with a star washer (to burst through the paint layer) on each side to ensure both sides of the panel are electrically connected (being composite, they have an inner polythene layer - nice capacitors
. Either a solder tag or a 'Lucar' spade terminal under the inside nut will allow connection to your ground busbar (which you installed earlier
). EVERY frame member should be grounded (or thoroughly checked for a good ground continuity at high current) - expecting the 25KV to jump across a gap doesn't cut it - it could just as easily jump across to your nether regions while watching the pretty light show - with dire consequences ! One of the benefits of using core screws is that the frame members have good connections to each other.
Seriously, system frame grounding is an artform (and a pita) - electrical inspectors have a heyday with system builders on this - to the point of being anal about it.