If we're talking early body style...
I've done the swap, and it's pretty straightforward. Remove the non-funtional "smoker" windows, install the functional ones.
There are two screws in the leading edge of the door that you'll need to remove, and I believe two rivets down inside the door, behind the "filler panel." You can use bolts to replace the rivets - anytime I drill out a door rivet, I just drill it out to 1/4", and use 1/4-20 stainless hardware to replace it. Make sure to use some sort of self-locking nut, so you don't have to go in and retorque the thing twice a year.
Also, make sure the channel on the vent window is properly aligned with the main window glass - once you get in there, you'll see what I'm talking about.
On the whole, probably 30-45 minutes per window to change, assuming the OEMR rivets are still in place.
5-90