I started out by getting rid of all the extraneous electronics. All You really need to keep the bike running are the battery, voltage regulator, and rectifier. I elected to keep the starter solenoid too. I usually kick started the bike, because it’s so much cooler, and believe it or not it actually starts faster. But electric start comes in really handy on the rare occasion that I stall it taking off from a light and I don’t want to stop in the middle of traffic and kick start my bike :).
The battery tray was the linch pin for the whole thing, so I mead that first from some angle stock. My idea was that I would try to hide the other electronics under it to make it look as stripped down as possible. Setting the battery tray on the frame, I held the other parts in the space beneath and tried to decide where they would go. I finally settled on welding on a tab that hung down to mount the solenoid, and then hanging the rectifier and regulator under the battery. I also bent some flat stock in the vice to make a bracket to mount the rectifier to, and welded some threaded rod on to mount the regulator. To hold the battery down, I bent up some rod and welded it on to make a bracket to loop a leather belt through.