In a medium bowl, dissolve Jell-O in boiling water.
Let cool 5 – 10 minutes or until slightly thick.
While Jell-O cools, using a medium bowl, mix 2-1/4 cups of the graham cracker crumbs with melted butter; press into the bottom of a 9-inch x 13-inch pan; set aside.
Reserve the remaining 3/4 cup of the graham crumbs for topping.
In a medium bowl, beat evaporated milk until whipped and fluffy; 2 – 4 minutes.
In a separate large bowl, beat cream cheese, sugar and lemon juice together until smooth.
Add the thickened Jell-O; fold in whipped evaporated milk.
Spread filling evenly over crust and top with reserved graham cracker crumbs.
Cover and chill at least 2 hours or overnight.
