Dell Optiplex 745 with BIOS 2.6.6 and SLIC

Multiple tries to patch SLIC 2.1 on Bios 2.6.6 resulted in HDR Checksum error. So requesting a friendly soul to help me out to mod this Ver 2.6.6 Bios with the following

-Manufacturer: Dell
-Model: Optiplex 745
-Bios revision: 2.6.6.
-Bios Type: Phoenix
-Bios Download Link: http://www.dell.com/support/drivers/us/e...2847999872 
Direct Link: http://downloads.dell.com/FOLDER00224415..._2.6.6.exe

If possible please use the SLIC from this mod as this one works on my computer with BIOS 2.6.4
https://www.bios-mods.com/forum/Thread-Dell-Optiplex-745-Slic-2-1