windshield gasket

I've never changed one before and I'm scared to death to break my windshield as it is perfect. The gasket on the windshield of my 72 Duster (the one in my avatar) is cracking up and I got the watermarks inside the car now. I already got the wiper arm seals from Schumacher so I guess I'll do it all at once. Waiting on the gasket from Dante's and I got a tube of butyl too as I remember reading somewhere on here that its cheap insurance. Is this a job for a novice??? I've built engines and done all kind of mechanical stuff but never any type of body/glass stuff next to changing a broken door window. Or is this something I should farm out to the Glass Doctor or someone like that???