Battery replacement for iPhone SE

I almost killed my phone again today. I didn’t realize that there are not just long, short screws in the phone. There are screws of different sizes: 0.12, 0.13, 0.16, and 0.17 mm just to replace the battery. I forgot how I killed my two iPhone 5S. But definitely, I didn’t know that there are so many different screws. I kind of recall that I know the difference between one demagnetized screw from the rest near the compass. The worse case is that if one uses the 0.13 mm screw for the 0.12 spot. It may damage the motherboard underneath. So I am not sure if that is how I killed the phones earlier. It took me a while to differentiate the 0.12 and 0.13 mm screws and the 0.16 and 0.17 mm screws. I basically shone the screw with a torch and tried to observe the minute difference in the shadow lengths. Anyhow, just to be safe, I didn’t screw in the 0.12 spot. The phone is working now, and hopefully, I don’t need to bother about that for a while (maybe after 2, 3 years later that I need to replace the battery again). And I lost two screws today—probably one 0.16 and one 0.12. There is no way I can find those screws again. They are so small that they are literally dusts. I didn’t screw in any 0.12 spots for all my phones. I left the remaining screws in the replacement battery-package insider the chair.