Hope the photos are clear enough to place the soldering iron in the right spot... ;)
Re: OLED: you bet it! it would be the perfect solution (i.e. longer battery life).
Problem is that research for an equivalent takes ages: at present I prefer investing my lockdown spare time (since February 23, greetings from Lombardy, N Italy) in playing on the QY instead of tinkering with it ;)
anyway, any advice on a potential (and cheap!) substitute is warmly welcome!
PS my mod also holds for the QY70 I hope... just hook to the +3.3V rail!
prea