Before we go any further I just want to let you know I work at a auto glass center and we deal with old cars as well as new ones. I have recently installed the windshield and back glass in my 67 cuda.
OK I know what you have now. Do you have all the clips on the car? Are the clips in good condition? The reason I ask about the clips is because they need to be installed before the glass goes into the car. What you need to do is test fit your trim and see how its going to "lay". You might have to bend the trim a little for it to lay correctly because whoever took it off might have warped it up.
The gaskets that you are using are they new or old ones? It is much easier installation with new gaskets because the rubber has not gotten hard over time so therefore it is flexible. If you're using the old ones just beware that you will use profane language. lol
You will use a rope on the windshield and back glass. It can be done without roping but it is much simpler job with the rope. I don't know about you but I'm all about making something simple.