Hello, my name is Kevin.
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Ok, i hope that you are talking about the suburban style & not the pick up version.
The easy way to get in there is the open the glass portion. Look down at the trim where the glass latch is & you will see a cover. Gently pop it off with a flat head screw driver. Remove the phillips screw.
Get in the vehicle in the back. Look at the door on the passenger side floor area. You will see the grab strap. lift the strap & remove the phillips head screw & then remove the strap.
The trim behind the glass area will pop down from the top (due not yank. be gentile). pop it down do the same to the sides.
Now lift the entire assembly approx. 2 inches up then pull back into the vehicle.
If you have done this correctly, the trim panel is inside the truck with you.
Remove the water guard. You will see the handle latch assembly. Remove the actuator rods & give them a good pull toward the opposite side (like the handle would).
This will actuate the latches & the door will open.
With the door open, reset the actuator rods with a slight tension & then retest.
Reassemble with the door open in reverse order. (Be careful of the glass latch.)
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