I did something similar, after finding the Bently procedure less than
exciting. (except for the excitement when the engine overheated in the
middle of the procedure)  Since I was using a cooling system flush
product that required draining and refilling the system three times, I
figured there must be a better way.

While flushing the system, I filled it up by making an adapter, out of
some tubing, and running a garden hose into the bleed screw hole.  When
it came time to fill the system with antifreeze again, I poured as much
as I could into the expansion bottle, then used a hand pump (the kind
that the local FLAPS has for $2 as part of a siphon kit) to pump
antifreeze in through the bleeder hole.  After this, it can be topped off
with water from the garden hose.  It seems like this is just like filling
a standard cooling system, using the cap on the radiator.  After driving
to work and back, I found the overflow bottle almost empty and topped it
off.  After that, it didn't seem to use any more coolant, although I
haven't dirven it too much since (thanks to clutch problems)

Bill