Your rear window is an easy fix. On your glass, I assume you mean you will have the original windshield and door glass cut to fit. I know that there are a lot of misconceptions about the door glass and some think it doesn't need to be cut when the roof has been lengthened, it really is, there is a thought out there that it doesn't need to be cut, it simply doesn't roll up as far anymore. This is untrue, the windows shape will have to be changed.
On that old truck, unlike todays cars the side glass is tempered and can be cut. But I have to tell you, it is likely a glass shop won't want to cut it for fear of it breaking. New glass isn't much and I would at the very least put new glass in the front. There is nothing like a new windshield to peer thru to make you feel like you are in a first class ride.