Why did you order new trim ? is there something wrong with the old trim ? installing the trim can be a lot easier using some mild dish soap to lubricate it so it will side in correctly ,You can simply wash the excess away before installing the windshield into the truck , Don't use any lubricant when installing the gasket to glass as it will want to slide off the glass . make sure the windshield is centered perfectly before installing .
1) gasket to glass
2) stainless trim into gasket
3) assembled windshield and gasket/trim into truck