Epson LQ-300 User Manual page 73

6. Insert the ribbon cartridge into the printer as shown; then
press both sides of the cartridge firmly to fit the plastic
hooks into the printer slots.
7. Turn the ribbon-tightening knob to help feed the ribbon into
place; it should not be twisted or creased.
8. Replace the printer cover.
After you install the color ribbon cartridge, run the self test as
shown on page 1-10.
Using the Printer
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