You're all going to have to accept the fact that you're basically going to have pay the $6 membership fee to have access to these files. I paid the price and it was completely worth it given the amount of time and headaches that were saved.
I got the Intel 7260 AC card here: https://www.amazon.com/gp/product/B00MY9S692/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
I have a Y580. My bios version was v2.07.
I downloaded the file named "[Y580][Y480]-'unlocked_BIOS'_660mGHzEdition_WhitelistMod.zip"
I got the error about the version not being newer than the current one I have, so I followed these directions:
Open platform.ini in notepad.
Find the line number 3: "SwitchString=ACEN DCEN CPVER:[1] FHRST RESSEN"
Change the "RESSEN" to "RESSDIS"
Save the file then launch InsydeFlash.exe.
Done.
Enjoy your new Wi-Fi card.