Do not remove isolator diode from
alternator,,,you will end up bleeding all your
battery voltage through the stator windings.
Not Sure about this : they is the retifer diode before the stator windings
so the courant must be stoped before
As to finding a switchable 12 volt source,,why cant you go to the key on power?
I to Check the The key On power (but as itis in
serial with the push buton) not sure to found 12 V