Arduino Network Shield With Non Standard CS pins for SPI

I have a non wifi standard network shield that by default was using Pin 4 for SD and Pin 10 for Network chip selects.

I have rewired this card to use Pin 47 and Pin 48 respectively for the Chip select pins.

Does anyone know what files i need to change to get the networking working with the new CS pins?

I have the basic example Ethernet Sketch loaded but it always reports an IP address of 0.0.0.0