swapping ecu's to k-pro

[typesarctic]

I have an 03 rsx type s and currently my ecu is stock. However there is another guy that lives fairly close to me and he is selling his rsx with k-pro. I may be able to swap ecu's with him so that i have a k-pro setup but I need to know what all I will have to do to make it work in my car. Will his immobilizer need to be programmed to work with my keys or will both the immobilizer and ecu need to be reprogramed or what?