The Yellow/Black wire on pin 8 of the passenger side barrel connector (X6011) is shorted to ground. I don't have a multimeter on me but my testlight indicates this ground is STRONG. It blows the 50A ignition fuse in the engine compartment fusebox. After disconnecting the ignition wire from the starter solenoid, the ground is gone.

Just replace the starter solenoid? They're pricey so I might as well ask before I buy one.

 

Do you mean the B+ wire to the starter solenoid or the relay signal wire?