Canon PC300 Service Manual page 100

Hold the cartridge with its Warning
label facing up, and rotate it. in both
directions about 90°.
Place the cartridge on a level place;
then, detach the tip of the seal, and pull
it fully out (about 50 cm).
Hold the cartridge with its Warning
label facing left, and slide in the
cartridge slowly until it stops.
Close the top cover, and return it to the
center.
COPYRIGHT © 1994 CANON INC. CANON PC300/320%25, FC210/290 REV.0 JULY 1994 PRINTED IN JAPAN (MPRIME AU JAPON) §-3