Re: French door grid removal
depending on the door some are made up of several peices of glass individually put in. newer models are sometimes just one large peice of glass with vinyl mullion trim glued to the glass with silicone..
one thing i will say is that this is not a diy project, your better off ordering a different slab for the door, this way all you have to worry about is the hinges, deadbolt hole and lockset hole lining up with the existing frame.. from there its a straight swap
fire up the saw and make some dust