68 Dart Gas tank removal

So on a 68 Dart, how do I get the filler tube out of the tank?

Cant pull it out through the qtr panel because on this year it comes up to the inside of the panel and screws to the panel from the outside.

Thought I would just leave the filler tube in place and lower the tank and slide it off. But it doesn't seem to want to slide off the filler tube. Don't want to wiggle the tank around and pull on it too much with it still connected to my qtr at the other end.
There is also a single small vent tube that's connected to the upper end of the filler tube, and goes down along the filler tube and through the piece of rubber that is screwed to the floor. I cannot see any sign of this small vent tube from underneath.

How would you go about this ?