It's not that difficult. Some call the sealant a bedding compound. I've never "roped" a glass in, but rather carefully insert the glass into the gasket and then Zipper up the rubber flap. Use lots of glass cleaner on the glass when setting it into the rubber. When you buy the glass ( a b-body windshield shouldn't run you more than $75 ) ask for a few of the plastic "bones". They'll help to shoehorn the glass in. Start at the bottom and work your way evenly up the sides... when it gets tight a gentle, flat palm, patting in the corners helps it in. Maybe there's some video's on you tube. Also.. on the rear, or any glass set with butyl, be sure to pre-fit the glass to determine the height. If the glass sits low you'll end up with a gap between the stainless trim and the glass. I use urethane but am sure there are still several sizes of butyl to choose from. Hope this helps.