[A/S] gasoline tank leak/smell with 1981 excella motor home

["rosendalemj"]

Hi,
I have a strong gasoline smell from the rear of my motorhome. The 
gas tank is in the rear, looks like some gas has run down the side of 
the tank. The generator has a line coming from the top of the tank. 
Perhaps it's leaking? 

This is hard to diagnose without actually removing the gas tank.
Has anyone encountered this before?

regards,

Mike Rosendale