"Can I replace iPhone 6S battery with a higher capacity one?"に関する回答You can get higher capacity batteries for the 6S now. I just installed one in my 6S last month which is putting out 2200mAh, as opposed to the 1715mAh it rolled out of the factory with. I have measured that capacity, I'm not just stating the manufacturer's claims. So yes, it is possible, but I don't believe they've managed anything higher than 2200 just yet.
"Printable iPhone 5S Screw Location Chart"に関する回答This is an instruction guide for replacing the screen in an iPhone 5S. Each time a screw needs to be removed they put the exact size etc in the instructions. All you need to do is scroll through each page to identify what you have. iPhone 5S screen replacement