Its on the top of the motor on the 7.3. Look 8" infront of your turbo and you'll see a round, black lid. Thats the fuel filter housing. Its also your water seporator. If you look on the back side (looking at it with you gut resting on the grill) down in the valley, you will see a small yellow lever. Its physically attached to the fuel filter housing. Rotate that to drain the bowl. Don't be alarmed if you happen to start it with out priming the fuel system (cycling the key a few time leaving the on for about 10 sec. each time) and it runs like sh*t for a few minutes, it'll clear up.