[REQUEST] Lenovo T420s whitelist removal

[REQUEST] Lenovo T420s whitelist removal
-Manufacturer: Lenovo
-Model: Thinkpad T420s - 4172-CTO
-Latest Bios Revision: 8CET58WW (1.38 )
-Bios link: http://download.lenovo.com/ibmdl/pub/pc/...uj18us.exe

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-Wifi Model installed: Intel Centrino N 6250

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-Wifi Model to install: Intel Dual-Band-Wireless-AC-7260

I see that this bios appears to be good to go for the T420s:

http://www.mediafire.com/download/7g0d6r...WW_NWL.rar

But I just want to be sure before I flash it.

Also, is it possible to flash back to OEM when I sell the unit, if desired?

Thanks!

-kj-