5.3 swap wiring question

[HotRodPayne]

do i need to use the big purple wire in the harness to the starter? cant i just use the original starter wiring front the factory harness to start the truck? i am using lt1swap.com while modifying my harness and i haven't read anything on the starter wiring. there is a picture on the site of a finished harness with the big starter wire rolled up and labeled. it has me confused. go easy on me this is my first time doing anything like this.