Hey! i sorta had the exact same problem when it came down to it. following Bens advise it turns out because the hinge broke on my old one the ribbion cable somehow "broke". Now that you broke it best thing to do is buy a New Top Screen off any online store that sells them. Ebay is were i get it! it works! oh, but remeber you need to disconnect the speackers and then Solder them back in. Its really not that all hard to do but yes it takes time too as well but in the end worth it! XD
OH and from a beginner point of view! See if the shell has been PreDrilled. The shell i got was REally nice. Only problem was tring to screw in the screws with the..well screw driver.

but it can be done. with alot of strength.