Gianluca
In picture immag015 you should be seeing +12v on the brown (+12v) and blue wire (ground/earth). However it is very likely your Camel has the 6v/12v system my kanguro had. This was, I understand, due to battery size issues. They had the alternator deliver +12v for the headlamp and then +6v for all the other electrics and battery. So you might only see +6v on the brown wire. Check the wires coming from the alternator as I would expect there should be a red wire as well. Initially check resistance across yellow & grey wire. The run engine and check voltage (AC) across grey and yellow wire. Then connect yellow/grey wire and check for output across brown and blue wire of either 6 or 12v (DC).
I initially converted my 6v/12v alternator to 12v and then not being happy with the resistance rewired the alternator to a conventional 350 spec, however I ended up with the same resistance. So the conversion is all you should need to do, it is at the following link:-
http://www.motomoriniclub.nl/6-Volt-conversion.pdf
The item shown in immag017 I do not recognise, I did not have this on my bike. Could be a relay or some sort of load resistor.
Your bag of dead wiring looks similar to my old wiring, on my rebuild I am using BMW K75 handlebar controls so also bought a wiring loom from a BMW K -series as a basis for a new wiring loom.
Good luck and keep us updated.
Regards
Robin
1984 Kanguro X1 home built special.
'Using yesterday's technology to create tomorrow's problem's today'