Kevin,
Nick is right. all the fuel lines between the fuel pump and the carbs are under positive pressure. I would check the float arms to be sure that they aren't bent. You might also check the float valve needle and jet. If that jet gets partially clogged it can cause low levels in the carb bowl. There is a pin about 25 or 30mm that holds the float arms in place. You can pull this pin out and the float arm assembly will come right out. One end of this pin is knurled and you want to be sure to pull or push the pin out in the direction of the knurled end. With that pin out, the float valve will fall out in your hand. It has a rubber tip which can be worn or damaged. More likely though, the jet that the float valve sits in is partially clogged. Usually you can squirt some carb cleaner and/or compressed air through the jet from the needle side and solve the problem. If the clog is hard, a small piece of soft copper wire will clean it out.
As for the fuel line, I use 20R6 or the high heat 20R7 fuel line. It's the same black fuel line thats in your car and it usually outlasts the car. If you want to go first class, get the high pressure fuel injection line. All of it is available at any auto parts house.
Bill