Anyone put a fuel cell in a 64-66 Cuda? Bad idea? Fumes?

The issue with a cell in the trunk is that you lose the trunk and when you fill it (if you don't hook up to the factory fill) you get fumes in the trunk when fueling the car which stink and can also cause a combustable vapor hazard.
Thanks for the input, an important point regarding hooking up the factory fill. I'm already now leaning towards the Tanks Inc EFI Tank.