i have a pre made tank approx dimemsions 3x3x3 feet the thickness of tank walls appear to be 3/16 to 1/4 inch thick. with a 1foot square opening on top for filling this opening had a raised "wall" approx 2inches. tank is used to collect used oil for shop heating. (this tank looks like a resturant tank thats in back to collect the cooking oil) currently useing a pump to move oil to and from(way to slow) thinking of have a "pressure" lid made with an air hose quick disconnect to blow/push oil from tank to storage vessel. suggestions? will this idea work?