Right now, I have a central live update server located at our corporate headquarters which downloads the virus defintions. I save them on a file share and it downloads ~6 GB a day of new stuff, and deletes ~6 GB a day of old stuff. 

I'm trying to share this directory with other sites in our company so they don't have to set up a liveupdate server, but the size of the directory is making it difficult. Is there another way of getting the definition files that won't take up so much disk space? I don't want to do it over HTTP.

If I'm using the network folder, then I can replicate that folder to other locations in our company that need it. 

any help would be appreciated!

Have you considered using GUPs?

Best Practices with Symantec Endpoint Protection Group Update Providers

They can provide the updates to your clients locally instead of coming back across the WAN.

Recommend you to configure the GUP. GUP is configure local on the remote branch where you require to update the client. The GUP role can be assigned to any SEP client. When assigned the GUP role, a SEP client will act as a caching HTTP proxy, storing both delta and full revisions of SEP content. Other SEP clients can be configured to utilize the GUP for definition and content updates via LiveUpdate policies from the Symantec Endpoint Protection Manager (SEPM).

Port 2967 is require to open b/w GUP client to other from firewall.

Configuring the Group Update Provider (GUP) in Symantec Endpoint Protection

• Article: TECH96419
• Updated: April 23, 2012
• Article URL: http://www.symantec.com/docs/TECH96419

Best Practices with Symantec Endpoint Protection Group Update Providers

• Article: TECH93813
• Updated: September 18, 2013
• Article URL: http://www.symantec.com/docs/TECH93813

New features and functionality in Symantec Endpoint Protection Release Update 5 (SEP RU5) Group Update Provider (GUP)

• Article: TECH96417
• Updated: February 17, 2015
• Article URL: http://www.symantec.com/docs/TECH96417

check the product selection tab, you might be selecting unrelated contents aswell.

http://www.symantec.com/connect/articles/liveupdate-administrator-product-selection-guide

Hello,

Check these Downloads which may assist you:

Script to download Definitions from SEPM

https://www-secure.symantec.com/connect/downloads/script-download-definitions-sepm

Script That Downloads .JDB Automatically

https://www-secure.symantec.com/connect/downloads/script-downloads-jdb-automatically

Note: Symantec does not support the above tools.

Hope that helps!!