Vette,
I can’t speak for glass, but other reproductions I’ve used like sheet metal, trim, seals, etc have all needed some tweaking. Some were close, some were almost perfect, but some were so bad that I actually threw my hands up and said WTF.
If you already have the glass, a glass shop should be able to help you out. You can grind ‘em down, but then you have to deal with all the dust and such.
If you haven’t bought the glass, take your originals in and have them cut you new ones to that pattern. I did this for my ‘51 one ton. It was so simple and fast. I got them 2 days later and they said they were behind schedule!
2 front windshields, 2 vent windows, 2 door windows, 1 rear glass= $440 Canadian.