The fuel lines goes from the drivers side frame, up over the engine towards the drivers side. - You will have to take the lines apart when you remove the valve covers and you will see them then.
You will want to blow air in the large line which is the feed line for the engine. The small line is the return line to the tank.
You should be able to find a leak if you squirt oil over the return lines and look for bubbles or fuel leaking out, but if you do not find a leak then you could just replace the return lines and seals.
PS: Some guys have taken the valve covers off, and then hooked up enough stuff to be able to start the engine and look for leaks while the engine is running.
Last edited by JoeSmith21; 08-13-2010 at 08:22 AM.