[REQUEST] Lenovo T420s whitelist removal

[REQUEST] Lenovo T420s whitelist removal
-Manufacturer: Lenovo
-Model: Thinkpad T420s - 4171-52U
-Latest Bios Revision: 8CHT28WW (1.44 )
-Bios link: https://download.lenovo.com/pccbbs/mobiles/8cuj22us.exe

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-Wifi Model installed: Intel Centrino N 6205

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-Wifi Model to install: AzureWave Broadcom BCM94352HMB

I've seen a few custom whitelist bios for this laptop, but I've searched for days and can't figure out how to downgrade the bios, and i have not found a whitelist bios for version 1.44. Help is much appreciated

thanks,

Charizard9000