The fuel dot is used to depressurize the tank when fueling; if you want to run an extra line with a plug, you can do this but you're adding complication to the system. The fueling valve is fine; simply install where you'd install the "TEE" for the fill line. The fuel dot can physically be placed adjacent to the fueling valve. Take a look at this for a pic of a fuel dot: http://www.dldesigns.net/dot2.htm
. A search on the 'net will net you all manner of fuel dots; take your pick. Make sure you have the check valve installed in the correct line and the correct orientation; the instructions that come with the engine outline exactly what is needed for the fuel system. Use 20/20 YS fuel and you're set to go.