Lexmark 2390 003 - B/W Dot-matrix Printer Service Manual page 87

10. Release the ground spring [11] from the end of the carrier shaft;
the spring need not be removed.
11. Rotate the left carrier bushing.
12. Remove the lever stop bracket from the carrier motor
(bracket not present on all machines).
13. Release the latch [8] and slide the carrier shaft and forms
thickness lever to the left and remove them together from the
printer. Do not to lose the gap set collar [15] attached to the
right end of the carrier shaft.
14. Lift the rear of the carrier [12] to disengage the carrier ribbon
drive gears, then remove the carrier. Do not to lose the oil felt
[14].
15. Be sure to get the carrier shaft correctly through the oil felt.
16. Perform the Printhead-to-Platen Gap Adjustment
see "Printhead-to-Platen Gap Adjustment" on page 4-2.
Repair Information 4-13