Thanks for all the info, Jock. Before reading your posts, I spent some time in the garage last night. With the help of my wife (she wants kudos for her patience while helping :-) I finally got the rear window seated.
Some other friends told me to lube everything up with silicon spray. Seeing that Armor All is mostly silicon, I used that to lube up the whole gasket, window edge and truck steel. The downfall of this approach is the gasket won't stay on the truck without some support. And the string just pulls out of the corners when I'm trying to install the window. Back to the drawing board. I put the gasket back on the window and went back to the string trick. By this time the swears are really flying.
My DW (Dear Wife) was patiently holding the window in place but couldn't seem to push hard enough to get it where it needed to be. We switched sides and she worked the gasket while I pushed the window around. Finally we got it in. But there is a gap in the gasket at the bottom. I guess my 1/4" wasn't enough. I have a fix for that though.
I got the locking strip in about 1/4 the way around before I gave up for the night. My fingers are killing me. I'll finish it up tonight.
As for the front window, I decided to go ahead and order the correct gasket. Might as well do it once and be finished with it.
My DW thinks I'm nuts becuase I've wasted hours working on these windows when she gave me the okay to call the local glass company to do it for me days ago. But I've found it much more satisfying to figure it out myself.
Thanks for the inpt guys.