The Airport icon would vanish from the toolbar on restart leaving me wireless-less, and major overheating from the Airport card!
Replacement card from iFixit and everything went brilliantly! But I'd been in the machine a few times before. Cinch with the iFixit guides!
The connector on one of the wires to the card wouldn't snap on. Very time-consuming and fiddly to get right. Make sure it all goes together BEFORE you put the replacement card in!