The fuel tank is under the right rear seat. It has an in-tank electric fuel pump. The supply/pressure fuel line comes out of the tank and follows the right side frame rail. There is an in-line filter alongside the frame rail under the front passenger seat. From there the supply line continues to follow the frame rail until it curves up the forward face of the firewall and connects to the fuel manifold at the right/rear/top of the engine. The second line that lies alongside the supply line is the return line to the tank. The return line is the one without the filter.
Both the supply and return lines are rubber or metal and should be visible along their entire length except where they enter the fuel tank. Check to see if the line burned through by touching the exhaust manifold. If it did and the vehicle didn't burn to the ground consider yourself lucky. Get under the vehicle and check the lines along their entire length. Any leaks should be obvious.
The hard, shiny plastic lines are either fuel vent lines, air suspension supply lines or axle breather tubes, depending on where they are and what they connect to. None of them should have any liquids in them.
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