Removing the interior door panel will not gain access to the clips. It has to be removed from the outside.
There is a multi-purpose tool kit made by OTC that Ford recommends - you can get it on Amazon for $20. OTC-4489. Ford recommended it in their TSB for panel fading, which also suggests tape along the body to prevent scratching when you remove the panel.
I'll also add that when I google the 4-door cladding repair kit part numbers mentioned below, I am shocked at how cheap they are. 4L1Z-78465K00-AAA for example. So not sure whats up with that or what the part number actually includes. Here is the TSB I spoke of:
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TSB
04-17-7 EXTERIOR DOOR TRIM MOULDINGS FADING - TITANIUM AND PLATINUM ONLY
Publication Date: August 20, 2004
FORD: 2003-2004 Expedition
ISSUE:
Some 2003-2004 Expedition XLT vehicles, (excluding Eddie Bauer models), built 2/1/2003 to 12/31/2003 may exhibit the front and rear exterior door trim and fender extension moldings (cladding) fading.
ACTION:
Replace all cladding on all four (4) doors and fender extensions. All cladding supplied in the Service Kit must be installed to prevent color mismatch and continued fading.
SERVICE PROCEDURE
Clean off the area below the character line and above the cladding. Remove dirt as necessary.
Apply protective tape (minimum width 1") directly above the molding. This will prevent scratches when moving the tool along the cladding to release (pop up) the cladding retaining clips.
NOTE: PAINTING WILL NOT BE APPROVED FOR THIS REPAIR.
Using Trim Removal Tool (OTC-4489), open the door and begin to pop up the nine (9) retaining clips across the top of the cladding and the four (4) across the bottom. Once the cladding has been removed from the body, remove the protective tape.
Install the new part (retaining clips are included on the new part). Repeat the repair on the remaining doors.
Remove the two (2) screws that attach the fender extensions.
NOTE: RETAIN THE SCREWS AS THEY WILL BE REUSED.
Install the new fender extensions reusing the original screws.
Return the vehicle to the customer.
PART NUMBER PART NAME
4L1Z-78465K00-AAA Medium Dark Platinum Cladding Kit
3L1Z-78465K00-AAB Medium Platinum Cladding Kit
3L1Z-78465K00-AAA Medium Titanium Cladding Kit
WARRANTY STATUS:
Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
OPERATION DESCRIPTION TIME
041707A Replace Cladding On All Four Doors And Fender Extensions Eight Pieces Total 1.4 Hrs.
DEALER CODING
BASIC PART NO. CONDITION CODE
7820878 81