(Addendum to previous post)
I got to remembering that hose clamp installation and how
nervous I was. Yes, when I took/pried the old clamp off,
took off the line and cut it, quickly stuck it back on,
and put on a new clamp, there was leaking trickle of gasoline.
The repair at the opening of the engine compartment didn't
leak while fixing, I think, because the fix point is above
the fuel tank, or above fuel level in fuel tank. The
fuel system has a fuel pump, I think, so the lines are
under slight pressure when the car is running.
A. ALWAYS keep a fire extinguisher nearby.
B. Be ready to run like hell and call the fire department
   (and say goodbye to vanagon.)
C. Proabably pay your mechanic to do this.