CAREFULLY...
Necessary removal to expose the window regulator.
-- arm rest: look for large phillips screws on the underside
-- windo crank, if manual: check out another thread in this
forum about that, using specific tool, or a rag.
-- upholstery panel: these are secured w/ push-in tabs.
slip a putty-knife between panel & door, then move
up/down to find a tab. When you do, gently twist knife.
Very likely will have to replace tabs, which can usually be
found at good parts stores.
-- there may be some kind of insulating sheet stuck on the
door frame. Usually not savable, but can be replaced
with plastic sheething (from Lowe's/H-D, get the thick
lawn/gargen stuff) and metallic duct tape.
This should expose how the window is secured into the regulator.
You'll probably have to move it up/down to get to the fastening
bolts. It will probably help if you have the replacement unit in
hand to see what needs to be unfastened. And be prepared to
find some assistance, cause the glass can be very heavy for
one pair of hands to manipulate while bolting/unbolting.
There, easy as pie...