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Like many others, I tore one of the ribbons on my iPhone 7 LCD assembly, do you have a guide on how to replace it. I have a couple of broken screens which I can use if I could get the ribbon off from between the LCD and metal backing plate.
The only user-removable flex on the screen assembly is the one for the Front Camera and Sensors. You can check out his guide. The other flexes (LCD & Digitizer) are embedded into the screen assembly. They can be removed but now your are talking more about screen refurbishment that repair. There are very few questions on screen refurbishment on this forum so you may want to search Facebook or Reddit, I’m pretty sure there are some dedicated forums on those sites.