People used to replace the 2 piece windshield in '49-52 Chevy cars with one piece Oldsmobile. A Google search might bring up info on that to see how it was done.
That was a windshield made up of two curved glasses, a totally different windshield than the 47-53 Pickup which was two flat piece of glass.
To the original poster, yes I have thought about the same thing on my truck. I am building a GM Motorama themed truck and the one piece 54 windshield is just what it needs, but yes it would take EXTENSIVE surgery. Now mind you, I have done extensive surgery including chopping and sectioning the cab and backed off on the one piece windshield idea. Though the truck isn't done and if one of those 54 cabs or windshield area comes along I may just go for it. But as of right now, it is just too much than I care to get into to for the amount of change I will get in return.
Brian