Check out this thread
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=668463&page=1

They give a few suggestions on sealant.

from what I’ve read here on the forum, sealing the glass should be the last step.

When I did my windshield on my 50
I installed the glass in the gasket on a bench with lots of Windex for lube
then installed the stainless trim.
installed windshield on truck, using Windex as lube around gasket area

you can use soapy water for lubrication instead of Windex

Then seal if needed


Good luck

DADS50
YouTube
1950 chevy 3100