Gunk in gas tank

[GordonP]

I'm trying to get a 29 Model A started.

The flow out of the gas tank is minimal. I've removed the shut off valve.

I know the car was parked for a number of years in a hot location, and I suspect gas evaporated leaving something that looks like shellac in the tank.

As far as i know, the tank was never sealed.

The goop around the the threads isn't hard.

Help

Please