You have to unbolt the wipers off the car then take off the cowl panel by either bolts or clips then the motor should be exposed then simply unbolt it.
tips: check the window weatherstrip
You better make sure to oil up those windshield hinges. When you are dealing with an older Jeep they are really good to get frozen up. That way when you bend the windshield forward you will have a bent windshield hinge. Go slow and be careful not to just throw the windshield frame forward.