Tips on O2 sensor removal in '83 CGT?

[Fisher, Scott]

Hey all -- time to replace the O2 sensor in the '83 CGT.  Stock original
intake and exhaust manifolds, no updates or mods.

I can SEE the sensor on the manifold.  I can spray penetrating oil
(silicone-free, of course) onto the nut.  I can even drop a wrench down and
just about get the jaws to line up on the flats.

But I can't get my hand through the space between the throttle body and the
plate that the battery rests on.

Time to buy another crowsfoot wrench?  (Alfa digesters will know what I mean
by "another..." :-)  Or is there an easier trick?

And assuming that an appropriately sized crowsfoot (on my 24" extension,
which I already own) gets it off.. how do I install the new one (or at least
get the threads started) if I can't get my hand down there?  Is there a
reasonable way to reach it just to get it started, then finish it with the
crowsfoot?  Or should I try to find somebody who has smaller hands?  (I bet
my 10-year-old daughter would be able to squeeze her hands in just fine!)

Thanks,

--Scott Fisher
  Tualatin, Oregon