Gardner I would agree with taking it to a business that installs Windshields. Be prepared to pay about $100 and most will not guarantee the re-install of an Old Windshield. Their reasoning is the windshield tends to get brittle with age and are pron to crack. Make sure you ask for their policy/guarantee. I was fortunate to have a local business who told me they'd put my old one in for $100 or a new one for $225. I asked, in the event they broke my old windshield would they charge me and they said no and could apply (credit) the $100 to a new windshield, so I rolled the dice and said what's there to lose. You can do it yourself but it takes a bit of effort. I've read one post where a gentlemen said he did it by himself (he's my hero) because it took me and three other guys.....I mostly prayed while the other three installed.....but we got it in and happy to say it sealed and we did not break the windshield.
If you decide to do it yourself and you have the Custom Chrome Trim around your windshield you must install the Chrome in the seal before you install. I fitted the seal onto the glass and then installed the chrome Trim, then installed. You will need soapy water to spray on seal and a strong 1/8" diameter rope/cord. We determined placing the bottom edge in place first, then tilting the top of the windshield in and under the brow of the cab (which took some effort) allowed us to get the bottom in place working equally up both sides and finishing at the top.
Search for tutorials online there is several out there. If you decide to do yourself and like a bit more detail, I'll be glad to help. I'm not saying my method is the best or correct....I simply know it works.