Only in the best of kits will the spring-loaded needle be found, but it is important for the float to work as designed. Another very important thing is the orifice size of the seat (the fuel inlet orifice). It ought to be about .80~.81" in diameter from everything I've read/seen. If you bought a cheap rebuild kit, the orifice will be made for Fords, and it could be as large as .93~.95". This may (probably will) cause flooding. What happens is the pump keeps pressure on the needle/seat. The float drops to the point where it allows gas in, however if the inlet size is too large, more fuel will shoot inside before the float can react and lift the needle back to a sealing position. So with a "too-large" inlet, you'll always have too much fuel in the float bowl.
