What backspacing should I get on the front? I don't want them to stick out at all, but I also don't want them to sit in too far. For the rear I am going 15x8 with a 4.5" backspacing. The front wheels will probably be 15x4, 15x5 or 15x6, whichever I can find. What would be the correct backspacing for each of those 3 wheels combinations. I have attached a picture of the appearance I want, although this car has 15x3.5 which is too skinny for everyday street driving. Thanks for the input.

 

Also, I need to know what the offset numbers should be as well. Thank you.