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ideally, the centerline of the tank should be within an inch or less of the carburetor (horizontally). this way the engine is not trying to suck fuel from below or above. This is especially true for beginners who do not have experience with glow engines. Avoid fancy fueling devices. they tend to cause problems (air leaks are especially difficult to deal with). run two line from the tank (one to carburetor and one to muffler pressure). disconnect the carburetor line to add or remove fuel in the tank. Keep the lines short -- no unnecessary loops, etc.

To get the tank at the right height, add some foam under the tank or construct a floor of light wood. Of course, the glow engines will actually run if the tank is an inch low or an inch high, but it complicates the starting procedure. when the tank is low, it is difficult to get the engine started because the fuel does not want to come up from the tank. if the tank is too high, the fuel will tend to flow down in to the carburetor even when the engine is not running (flooding the engine).