Back window doen't go down, so I cannot put tailgate down. Do I need to put tailgate down in order to change tail light?

 

I know on my 89 the tailgate doesn't have to be down, but you're a 91 so I'm not sure. You should be able to tell by looking at where the screws are located. Usually, you can just take the lens off, and the whole reflector and light assembly comes out. Mine is like 6-8 screws on the lens.

 

YUP. the two screws to remove the rear taillights are in the Tailgate door jam

Have fun

 

looks like your going to have to troubleshoot your window issues before you can get to those 2 screws and fix your taillight.. that sucks. good luck

 

Try this...take the rear carpet panel off, remove the metal panel, apply 12 volt power directly to the window motor and lower the window. It may be as simple as freeing up the sissor (sp) arms that raise and lower the piece of glass. Drop the gate, change your bulb (both sides) and then fix the reason the window won't move.