1. Where is there a good switched power in the engine compartment

     2.when the power is switched on, pins 1 and 13 see 12v.  1 comes
from the AEM hall unit and when grounded shows just under battery
voltage, and 13 is from a relay which shows battery voltage.  Does the
power coming in from the hall unit do anything in the ecu or does it
just tell the ecu "hey, i'm powered on and functioning".

I am in the process of converting to megasquirt and have all issues
resolved except for the switched power and where to connect the ~+12v
coming from the hall unit.

Thanks in advance.
Sudhir