The red is your power for the alternator. The other you don't need to hook a wire up. Well, it might be the ground actually.
2004 Nissan Titan Crew Cab
1966 Ford Mustang Original 289
Edelbrock RPM Performer Heads; bored .30 over
Weiand Stealth Intake, Holley 600 CFM Carb.
Comp Cam 268H 9.5:1 Speed Pro Pistons
Patriot Tri-Y Headers w/ 2.5" H Pipe, Flowmaster 40S
620 1" drop in front, CSRP Front Disk Brakes.
Ford 8 3.40 trac-loc rear end