If your tank is in a location that may be easily reached, how about a pressureless balloon tank. Typical party balloons don't have good longevity WRT fuels, but nitrile gloves are normally pretty resistant to many chemicals, can be purchased in various thicknesses and are cheap (not to mention, you'll get 5 tanks per hand.
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You get fuel flow in all attitudes, no foaming and they will empty out fully.