To remove the front panel of the Canon 9000F, release the plastic
tab/hook in the lower center part
at the front of the scanner, then
slide the black part upwards in
the direction of the glass bed to
remove it.
(Some force are needed here to over power
some snap locks)

Now remove the two screws that
are holding the lid of the scanner.
One in each corner.

Then lift of the lid to reveal the
two hidden screws that has to
be removed to allow the glass
bed to be lifted off.

Be careful not to damage the
ribbon wire that connects the
lid to the main part of the
scanner.

It is possible to disconnect the
ribbon wire but it is not
necessary for the cleaning
process.

Screws holding the glass bed
can be unscrewed when the lid
is lifted away from the scanner
body.

 

Above: At this stage the 4 screws by the lid hinges is removed, the front panel is
also removed and put aside. Now carfully use a thin strong plastic or steal blade to
gently unlatch the snap locks around the edges of the scanner to remove the glass.

This was the part of the
de-assembling that felt most
scary however in the end it
showed to be less dramatic
than in first appeared to be :0}

Now we are inside the scanner so I hope you chosed a dustfree envoirement for
your scanner surgery, the cleaning can now be performed.

Start with a soft brush and compressed air to remove most of the dust, this
prevents the dust from contaminate your cleaning cloth and helps to avoid
to get scratches on the scanner glass during cleaning.

I suggest that you use some disposable sealed Wet/Dry Screen Wipes for the
final stage of the cleaning for the best possible result.

An alternative cleaning solvent could be 100% clean isopropyl alcohol
(I know that isopropyl does have a repurtation of leving streeks on the glass but this is only the case if it like in
many cases contains oil)
or some kind of spectacle lens / glass cleaning solution and a soft lint free cloth.
If you want to stay on the safe side get one of the Scanner cleaning kit's sold
by Amazon

Make sure to have two clean cloths on hand, use one to put a small amount
of cleaning fluid on, wipe the glass clean with thae moistured cloth and use
the 2nd one to wipe it dry to avoid streaks.

On the inside and upper part of the scanner glass bed there is a white stripe
(witch I forgot to take a photo of but the one below is taken from my 9950F and looks pretty much the same).
IMPORTANT! MAKE SURE NOT TO DAMAGE OR MISCOLOR THIS STRIPE IN ANY WAY.
If you do it will end up with a mess since if the calibration stripe is damaged you
will probably end up with a scanner that can't be properly calibrated so be careful
and don't use to much cleaning solvent.

On older scanners it is common that they develop faults like discolored streaks,
the source for those problems is not unusually a dusty or by age miscolored
calibration stripe.

To the left: The calibration
stripe should be kept dry
and dust free other vice
you might ruin your scanner,
be careful!