Black screen after replacement install

I see other people have had an issue similar to this. I had a cracked screen originally on my 3XL. Bought a replacement, and installed per instructions and installation via the iFixit website. I followed everything step by step, and still seem to be having an issue with the screen coming on. Another user had this issue, but fully assembling the phone resolved the problem. I have attempted that, and still no resolution. I attempted this fix as it was much cheaper than taking it into a shop, and I would like to avoid that but if I can't get any help here I may have to bring it in.

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I made sure to attach the screen before plugging in the battery. The screen seems to respond to touch, and the phone sounds when plugging in the charging cord. I managed to unlock the phone through guestimating where the buttons were and got the flashlight on. I sent off a request to iFixit for a replacement. Fingers crossed it was just a bad screen.