Just to add now people... I've uploaded the stock Telstra KF4 ROM including the Kernel and Modem here:

http://www.filefactory.com/file/c4c2...100TTELKF3.exe

It WAS originally located here:
http://forum.xda-developers.com/show....php?t=1113928

These are the install instructions:
http://forum.xda-developers.com/show....php?t=1075278

Hope this helps fellas!
Samsung Galaxy S4 GT-I9505 - ROM: Goldeneye 35 - PHONE: XXUGNF1 - KERNEL: GoogyMax 3 1.0.8