Not sure if there is more than one supplier for the chrome hinge for the quarter windows on a 69-70. So it might not make any difference
Believe the instructions suggest that you may have to warm the assy up to get it apart (window from the gasket and frame) but this time of year it will likely not be required. I just pried carefully ( a little at a time from each end) between the gasket and the old frame.
Putting it back together I lubed the gasket with some window cleaner and helped it into place with a small 2x4
Believe the gaskets were a pain since we ordered them a number of times and kept getting only one side (two of the same side)