07 Tahoe engine replacement

[robgreg75]

My son has a 07 Tahoe 5.3 4x4 and a shop told him it needed a new motor because that cylinder shut down system was turning off one cylinder without doing very much testing on it, I told him probably needed to have the delete parts put in it and get the computer flashed but he didn't want to listen to me so this Saturday he is bringing it down with a new remanufactured engine $4,300 hundred later, so is there anything we should do or watch out for while do this engine change. Thanks everyone in advance.

How many miles did it have? Seems finding a used engine would have been cheaper.