Ok cool thanks guys, I honestly dont even get why you would want to run 15" rims anyway, except for cheaper tire prices lol
More side wall too. You do end up saving about $100 per tire. So that can add up if you plan on keeping the same size tire.
If you want to run 15's, you need to get 3.75" backspacing or less. Any more than that and you will have problems.
My wheels are MB TKO 15 x 8 with 3.75" bs. There are quite a few choices for wheels that will work, but not much of a selection compared to 16"+.
If you want to keep his tires and get new wheels, let me know. I have a list of wheels that will work.