The larger clips go on the bottom of the windshield.
I just did the front and rear window of my 68 Roadrunner and used the 5/16 3M glass tape on the rear. It worked fine.
My glass guy also applied a liquid sealer to the perimeter of the tape to prevent leaks. He normally installs the stainless trim at the same time to be sure the glass is not too high for the trim. (pushing it down as needed).. My trim was still being polished and I installed it later, but it came out fine with the 5/16 stuff.