This Power Window Motor is from a 1960 Thunderbird.  There are slight internal improvements in the '60, so the 1958 and 1959 Squarebird motors have differences.

Picture #1    The two long mounting screws were removed for easy wheel access.  Before attempting disassembly, BE SURE there are no dents or raised metal (dings) on the motor shaft.  A ding will hang up on the bearing, causing unnecessary damage and a mad scramble for specialty parts.  Use a fine file or die maker's stone and go over the shaft surface.  Any imperfections will show up immediately.  File them smooth.  The housing shell should easily slide off of the motor shaft.

Picture #2    This is a (3M)ScotchBrite wheel, not a grinding stone!  The purpose is to remove paint, rust, and scale, not dents or dings.

Picture #3    File the set screw marks so they aren't raised and gently tap the bearing off.  If you feel resistance and the front shell doesn't easily remove, look for an obstruction on the motor shaft.  Continued hammering will destroy the nose bearing parts.

Picture #4    Here are the parts laid out.  This is really an "after" picture, shown to keep track of the washers as they help control end play and center the armature (and brushes) inside the housing.
 

Picture #5   This is the armature before the commutator segments are cleaned-up. This commutator shows evidence of excessive oil or grease, but a careful inspection shows no burned, scored, or tapered segments.

* Commutator segments are made of soft copper surrounded by micarta or bakelite. The brushes are made of carbon-impregnated bronze.  This combination serves many purposes:
  The materials are heat resistant because brushes run hot from lots of current and arcing.
  Brush carbon forms a lubricating surface on the segments that current easily passes through, so motors should last many decades.

Picture #6   I zoomed-in as far as possible to show the commutator silhouette.  I want to see the contour of these segments.  This one is nice and straight so cleaning is all that is necessary here.

As a LAST resort, a disfigured commutator can be 'trued' by tooling the copper down on a lathe, but the lubricating carbon 'skin' will be gone from the surface and the micarta will need to be undercut with a knife.  Then, the brushes should be arced to match the new commutator radius (do this by hand with very fine sandpaper on the commutator).  Further 'break-in' will sacrifice some brush length.

Picture #7    Nicely cleaned field coils and brush holder plate.

Picture #8    This is an excellent image showing the brush holders and solder pads, where all the wires are soldered.  Ford kept the integrity of using colored wires for positive leads and Black for all ground wires.

Picture #9    This image shows the sintered oilite bearing (on the left) with a surrounding felt 'oiler'.  The reason it is out of the nose bearing holder (top) is because the motor shaft had a bur and excessive hammering destroyed the bearing spring.  The replacement spring is on the bottom right.  Normally, this bearing assembly should not come apart.

Picture #10 (from Mike Gaffney (gaffney1951))     This is a broken brush holder plate from a pre-1960 motor.  Mike used epoxy to repair it.

Picture #11   The yellow wire feeds the UP field coil, the red feeds the DOWN field coil.  Both coils exit with black wires.  Eventually, all black wires will connect on the solder pad attached to the brush holder plate.

Picture #12   

Picture #13   

Picture #14    This is a good picture of Martin Burs's hand.

Picture #15    Before installing the armature, use 'T'-pins (available at any hobby store) to hold both brushes back.

Picture #16    This armature was cleaned, turned down, and now the commutator segments are being undercut by removing micarta between segments with a knife.
 

Time to reassemble and paint this motor.  Below is the electrical schematic (including the switch).  The motor is shown within the dashed lines.

Picture #17    Squarebird power window motors are DC shunt motors.  Ford kept this configuration in Thunderbirds through 1962.  In 1963, Ford used three-wire series motors.