How has the limitations with the ffr fuel tank been resolved by 818 builders?

My issues: tank is hard to fill and I am only able to get to 1/2 tank before fuel begins to run out of the vent or overflow the fill tube. I also experience the vent line spitting fuel when it was ideling for about 20 min. I know it only accepted about 8 or 9 gallons before this started because I used 2 5 gallon cans to fill it and it would not take the second can.

Any help is greatly appreciated
Dedrick
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