Well...I just replaced my 240Z windshield with a new tinted version I've had in storage for a year. Here are some photos of the mysterious and scary process of using a rope to pull the surrounding gasket into place.
To begin I put the gasket in my sink and lightly scrubbed it with hot water and dishwashing liquid. This removed any residues and mold release compounds...as well as making it more pliable and easier to fit around the glass.
I bought a spool of 3/8" polyester rope to use. Its a bit stiff so I twisted it a few times to loosen it up. Then simply work it around the edge under the inside groove.
Tape the ends in the center bottom. Then liberally spray a water based "Armor-all" style lubricant around the whole perimeter of the seal/rope and well as around the lip on the car body.
Then with a friend helping fit it in place in the car's opening. The bottom rubber lip will fit over the car ledge as shown below.
Then simply start pulling the rope out a few inches at a time, I alternated side to side. I used a small "L-shaped" metal pick to pull the rubber edges over the lip in places...this small tool saved probably an hour of cussing. Having a friend push at the beginning helps get the lip started, but not too much pressure was needed. Once you round the bottom corners the gasket seemed to pull itself to car body. When the ropes meet at the top center they simply pop out.
I had to run my finger under the edge on the outside all the way around as some places had slightly rolled under. Took just a few seconds to fix.
Not too many other tips to mention...the entire process took about 20-30 minutes. Not a single problem encountered except having to clean the window several times afterward to get all the protectant off.
UPDATE: I decided to try to put in my rear hatch glass by myself. Using the same method as the front I was able to put it in in 20 minutes no snags or issues. This seems so daunting beforehand...its really not.