need help with MSD 6Al box wiring

Not to familiar with you car but in general you could look at alternator excite wire for key " on " power.For " Cranking" voltage look at Starter solenoid for a terminal that powers up during cranking proccess for ignition boost . Find the solenoid terminal ( purple wire maybe ) for cranking voltage on starter solenoid. There should be many places for key " on " voltage . Hope this helps , i am new here and a boat mechanic so i could be way off base here . Maybe at least some one will come on tell you the right method ...lol