So electricity is magic and I'm not a wizard.
I'm gonna post my current wiring setup, and ask for constructive criticism. Frankly, I want to learn what I'm doing wrong, cause last time I thought I had my wiring totally solved, I ended up electrifying the whole frame. Yikes.
I got a bit of grounding advice from Rebel Moby among others, and revised my setup some.
So here it is, a NOS peugeot harness, modded to work with a Ducati energia cdi, a halogen headlight, and a LED taillight (Treats' "vertical fixation")
The headlight bucket has a ground from the headlight, kill switch, and brake switches, just like stock, and the taillight has a ground to the fender, as stock. The LED light's wire colors are a bit counter-intuitive, but it's wired up correctly per Treats' instructions.
From Rebel Moby's advice, the engine ground strap, cdi box, voltage regulator, and frame harness are all grounded on one big bolt on the frame, with nice shiny paint underneath. The zip-ties on the plug wire are a trail-tech tachometer.
The only thing I'm missing currently is a rear brake light switch, cause my left side control doesn't have the hole drilled to install it.
Thanks for the help you guys! (edited)