My favorite addition to my Scout Sixty!!!!!!!
Also available at ANY parts store and Wally World.Heat gun to form shape with tank. Clear RTV silicone Adhesive / Sealant. Took my time heating and shaping until it was a good fit for seal on the tank. 24 hour cure to get a great seal.
Amazon.com: Permatex 80050 Clear RTV Silicone Adhesive Sealant, 3 oz: Automotive