Got my 12" Factory 47 installed. Ordered them on Wednesday got them on Friday and installed them on Saturday. Was not to bad, couple of hours with a few breaks. Got "hungry and thirsty". Pretty happy with them, will take some getting used to. My front end feels so much lighter I am wondering around a bit in my lane. Take off is also different due to the lightness feel of the front end. In time my muscle memory will take over but till then I just have to pay a little more attention.