Replace LCD Display Screen for Metro PCS LG Optimus M MS690

I am trying to replace a LCD screen or maybe possible a Digitizer. I'm not sure which i really need. I have never replaced a digitizer or LCD. I have found a few locations to purchase both but i would like to know a little bit more about the process.

Thanks
Digitizer or LCD Display Screen for Metro PCS LG Optimus M MS690

 

I found this eBay listing not sure if it is what i am really needing. I just am unsure of the pressure point on phone to be able to snap open after removing all screws. When i try to open by applying a prying motion it just feels like I'm going to break the outer casing. I know sometimes there are hidden tabs that hold two molded front and back together. I wish i knew there location to be better able to open with out breaking phone.

LCD Display Screen for Metro PCS LG Optimus M MS690 | eBay

 

Thanks. I see that there is a digitizer and an LCD screen on that site. What is the function of both.The front of my Optimus M has no cracks on front.
It seems like the inner part of the screen has been distorted.
The screen light comes on and that's when i can see the distortion but nothing else.


Any help is appreciated..

Thanks

 

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