This is my first gn,so please bear with me...LOL...I have some questions about the fuel system...I bought the car with a spun bearing,the motor is out and at the machine shop,just going through the car and noticed there is a black holley external fuel pump mounted in front of the tank on the bottom of the undercarriage and there is a pump in the tank also(not sure which one,stock or aftermarket),any reason for two pumps and how does the external one work?Cant be on all the time,can it?I dont see any switches or controls to turn it on.Should i drop the tank and install a walbro 340 and do away with the external pump?Any help would be great.