Wiring: because the electrics were totally butchered I had to make a new loom:

This is what was left of the old loom. I found a wiring diagram on the Ducati scrambler website
I had to make a new one. Not expensive but time consuming, drawing bundles of wires through the sleeving.

Before committing to lengths I fitted the entire loom, so that I could prove that everything would work hopefully! Although the bike has a nonstandard regulator I decided to make the loom as original and add a couple of spares for good measure!
 
 
  My first sight of the aftermarket regulator did not inspire me with confidence. Despite my initial misgivings once I drew out a diagram and did some rudimentary tests. I found that all the parts still functioned. However all the soldered joints needed resoldering due to vibration / excessive heat or because they weren't done properly in the first instance!( most likely) The unit has to be insulated from the frame as the transistor can and the heatsink are positive.
 
 
WIRING DIAGRAM
DOWN LOAD WIRING DIAGRAM

Regulator schematic (NON STANDARD)
DOWN LOAD REGULATOR SCHEMATIC
OK it all worked even down to charging the battery so lets make it a half decent fit before pulling it apart again!