Hey all,
Today I bit the bullet and pulled the firewall on my '78.  It turned out to be
not too difficult.  

I removed the charcoal canister (mine's in a weird place), the decel valve, the
voltage regulator, the series resistance block and double relay, the air
cleaner/intake air sensor and that flexible rubber boot that connects the intake
air sensor to the throttle body.  Also took out the batter since I was in there
anyway and filled it up and put a charge in it.

On my bus there were only the six screws in the engine compartment to deal with
and the firewall came right off.  Looking inside, I could see the holes for the
two screws underneath but they were not installed on my car.  

Pulled the firewall back and let it rest agains the heater blower and examined
my gas tank.  Dusty!  I didn't see any gasoline tracks in the dust, the elbow
that connects the filler pipe and the tank seemed to be in good shape and was
sealed with what looked like silicone, looked pretty leak free.  Probably has
been replaced before.  Looked newish.  I replaced the four 7-mm hose vent tube
connections, two on the tank and two where the yellow plastic tubes connect with
the metal tubes that go into the air scoops.  Was kind of a pain, but I think it
was worth it.  They looked kinda old and possibly leaky so maybe that's where
the smell was coming from.  Hopefully the new hoses will stay on there 'cause I
don't really want to do that job again unless I have to.  

Put everything back together and re-hooked up all vacuum hoses, etc, and the
thing started before it could even turn over once.  I love fuel injection :) .

Not a bad job, took maybe around 3 hours total including a break for lunch,
fairly straightforward.  

Next time I fill up, I'll let you all know if the gas smell is gone.  

Sean