FWIW - Gladney Automotive is my shop and with aftermarket parts, they have no problem installing. My clutch that they did is a good example. They asked me what I wanted in their and noted that with tuned power and IS38, that they would not recommend a stock clutch, nor would they want to do that (like I said, they are always in the "know"). They recommended the stronger version of my ACT clutch and I asked if they would install. They said of course as long as they order it themselves. I'm ok with this myself, sure I can't buy it and they install it, but its next best case scenario for me. We even discussed engine build and the guy states simply bring me a list of what you want in there, and we will take care of it, and of course share prices of what each part cost.