Hello,
Well, I attached how to remove and replace the back window. Hope that helps. Also, it appears that this may be a common problem as they have a technical service bulletin on it. I have provided that also.
Removal:

Remove the rear seat back.
1 Remove the bolts.
2 Lift up to remove the rear seat back.

Remove the safety belt guide bolt.
1 Lift the cover.
2 Remove the bolt

Remove the roof side rear trim panel.
1 Remove the pin-type retainers.
2 Pry and release the clips.
3 Slide the roof side trim panel out of the retainers and remove the roof side trim panel.

Remove the coat hooks.
1 Remove the two screws.
2 Remove the two coat hooks.

Remove the dome lamp.
1 Carefully pry the lens out of the dome lamp.
2 Remove the dome lamp screws.
3 Remove the dome lamp.
Lower the back half of the roof trim panel.
Cut the foam butyl from around the back window glass.

Remove the back window glass.
1 Remove the 12 nuts.
2 Remove the back window glass.
Remove any remaining foam butyl from the window glass frame.
INSTALLATION :
Clean the back window glass with an alcohol-free cleaner.
Apply 8 mm foam butyl, or equivalent meeting Ford specification WSB-M2G234-C to the back window glass.
Start at the bottom middle and work around.

Install the back window glass.
1 Position the back window glass.
2 Install the 12 nuts.
Position the roof trim panel.

Install the dome lamp.
1 Position the dome lamp.
2 Install the dome lamp screws.
3 Install the lens.

Install the coat hooks
1 Position the two coat hooks.
2 Install the two screws.

Install the roof side rear trim panel.
1 Slide the roof side rear trim panel into retainers and position the roof side trim panel.
2 Install the clips.
3 Install the pin-type retainers.

Install the safety belt guide bolt.
1 Install the bolt.
2 Install the cover.

Install the rear seat back.
TSB
Article No.
04-2-2
02/09/04
BODY - BACK GLASS - SLIDING BACK GLASS
WINDNOISE/WATER LEAK - SEAL REPLACEMENT
FORD:
1999-2003 F-150
ISSUE
Some 1999-2003 F-150 vehicles may exhibit windnoise and/or a water leak from the back glass area.
ACTION

To service, order and install Service kit 3L3Z-1542052-AA. Refer, to the installation instructions included in the kit. It will also be necessary to obtain a tube of Motorcraft Instant Adhesive (TA-19) or equivalent for this repair.
NOTE THE KIT APPLIES TO BOTH MANUAL AND POWER SLIDING REAR WINDOWS.

Parts Block
OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
OPERATION DESCRIPTION TIME
040202A Install Backlight Sliding 0.6 Hr.
Seals (Includes Time To
Remove Rear Seat Back
On S/Cabs Vehicles Or To
Loosen Upper Portion Of
Back Panel On Regular
Cab And Super Crew
Vehicles
DEALER CODING
CONDITION
BASIC PART NO. CODE
15420A26 33
Nov 11, 2008 at 2:20 PM