You
definetely have to use baking soda, its purpose is to
neutralize the acid, otherwise you are just spreading the acid around.
Either way do it away from any area that can be stained, specially concrete driveways.
This diagram should match if you have the CVP (Continously variable Potentiometer).
http://www.buggiesgonewild.com/attac..._96_ds_cvp.jpg