Here's a good article on installing one in a CJ.
Jeep Glass Windshield Installation - Offroaders.com 4x4 off-road trail reports, tech articles, 4x4 clubs, offroad links
The windshield is actually part of the structrual integrity of the vehicle. You want to get it right, and without breaking it of course.
But for what it would cost you to have an installer do it, you might consider just having them put it in.
Little things, like a teeny tiny bur on the frame can cause your glass to crack. If it's not properly sealed, it will leak. If you don't hold your mouth right and stand on your left foot it can jump to it's death right there in the driveway.