Bios Mods -The Best BIOS Update and Modification Source

Hi,  I am looking to see if it is possible to mod the bios for the stock Dell Precision T7500 motherboard to allow overclocking of the Xeon CPU's,  I am hoping to be able to lock the Multiplier to the maximum it will allow and possibly FSB overclock as well.  If nobody can do this can somebody lead in the right direction to learning to do it myself? I am also hoping to be able to modify the bios to allow SLI without having to hack the NVIDIA drivers.

Product Name: Dell Precision WorkStation T7500
Main Board ID: 06FW8P
System BIOS Type: Phoenix
System BIOS Ver: A16

Official download: http://downloads.dell.com/FOLDER01514282...500A16.exe