I don’t have a PIR sensor to fiddle with … however, why are you setting pin 3 HIGH, and as an OUTPUT? If it’s to power the PIR sensor board, don’t, use either pin 1 or 17, those have a constant 3v3 on them (or if you know your sensor can tolerate 5V, use pins 2 or 4). If it’s to read from the PIR sensor, it needs to be set as an INPUT pin so it can detect when the sensor triggers it.
Is there a way to install Pi Music box in the background, without having to put the whole image on my memory stick and overwrite what I’ve got for my MM?
Or is it worth just putting Music box on first, then installing the mirror?
I want to be able to play music through it as well as use it as a mirror.
Standard through hole resister, probably wouldn’t need anything above 1/8 watts. I have a few thousands of those in different values … as well as SMD ones.