** also remove the small Phillips screw fastening the WiFi antenna to the top rear casing of the phone

is this bracket a must replace part, or if damaged/removed, will the camera still function? My only option to replace seems to order from HK and wait 20-50 days ....

If the ESD plate covering the connectors is properly re-attached to the phone, you should not have to do this. The cover holds all the connectors in place just fine.

In reference to your #1 point, this is very good example of why a SCREW-MAT or iCracked Part Chart come in very handy!

Especially in repairs like the 5s ... some screws look the same, but are .01" different ... enough to scratch/break the trace underneath on the logic board .... adding another $100 (and a week travel time by mail, if you cannot do the repair yourself), to your repair - to have it micro-soldered.

With Screw-Mats or iCracked Part Charts, every screw is placed on it's corresponding marker, so you know exactly which screw is which.

If you are in a pinch, and do not have a Screw Mat, you can draw little diagrams on a piece of paper or a dry erase surface, and mark out where each and every screw goes, as sometimes there is that .01" difference in screw sizes, that can really screw up (no pun intended) your repair.

Cheers!