Chosen Solution
I’m talking both the 6 Y000 to the sides and the one philips next to the Touch ID. Unfortunately they are not mentioned in any guide with their respective length.
The guide for the iPhone 7 Plus states that it uses 1.1mm Y000 for the 6 shield screws and one 1.8mm philips. Since most of the other screws seem to be the same length my guess is those will be identical as well.
In this guide you will find all of the screw lengths for the screen assembly, except for the 6 identical screws securing the sides of the backplate. By exclusion, you should be able to figure everything out.
