How to install BE 2010 SP3 w/o Internet Connection

Hi,

I have a server running BE2010 without an internet connection, so LiveUpdate fails.  I need to install SP3.  Can someone point me to the instructions for installing a SP manually through LU?  If not, can I install it manually without using LU? Are there any issues with installing SP3 manually without LU?  I am asking, because I did see one thread where someone did a manual update of SP3 and BE2010 didn't see it.  

FYI - I am not eligible for Symantec support, so callnig them if I run into problems is not an option.

Thanks,

Linda