i have a 07 Silverado southern comfort with the 4.8 v8 i have a set of 853 cast heads i want to put on my truck and im not sure if i have to put the ls1 waterpump on or not and also if i have to have remap my computer on my truck or can i just go out and buy a aftermarket programer... and when i get ready for the swap im going to swap out my cam.. i want a mild cam and not what would be the best combination cam and lifters for these heads