There's a reason why you don't see gas tank filler necks at knee level anymore. They are a pain in the ass to fill, AND they are a bitch to vent. I played hell with mine like everybody else. As was said, that whole loop deal doesn't work. It just makes the tank belch and does a poor job of venting. A canister in the trunk and back out to fresh air is the only way I made mine not spill gas even at full tank. You could get all factory and put a pressure sensor/solenoid into a charcoal canister. To much work for me. I agree, Rick should really know how to vent his own tanks. A proper fuel level sensor would be nice as well.
That being said, my tank has been good to me. You just need to tweak it in like many other things.