I actually did the reverse (free solid window, cheap, noisy rear slider, cool Colorado air /forums/images/graemlins/smirk.gif )
I just started at one of the upper corners on the inside with several flatblade screwdrivers (shorter and wider are better). Worked my way down the side and then started alont the top... pretty soon the window was out.
Pretty much reversed the scenario from the outside to install (starting at the bottom as I recall). Might have had the neighbor help for a few minutes during the install.
Whole thing was less than 1 hour.
That said, I do believe the advertised install method is to put a rope around the seal (where it holds on the opening), hold it to the cab point and pull the rope straight away (from the inside). This pulls the gasket "flap" in so it is out of the way to slide into the opening. Definitely a 2 person operation (and probably doesn't make any sense from my description... I be engineer, me no communicator).