So I’m reinstalling some Macs here. I’ve sold my MBA 2011, formatted my cMP 3.1, and my cMP 5(4).1 is waiting for new parts. The only operative Mac atm is the other half’s MBA 2012 which has got a clean install to Mojave. So - how the heck to I now reinstall El Capitan on my cMP 3.1? I can’t find a way to legally download El Capitan from Mojave.