Installing the intercooler diverter at the same time as installing the fog lights makes sense to me. The first board member who did the fogs himself said if he had to do it again he would have the dealer do it, but I am pretty sure I would not want a dealership installing something like the intercooler diverter unless I was buying the product from them. He also posted in detail what he had to do, including removing the front bumper fascia, to get the job done, in a thread on this board.
Laborsmith