You said they have "5 on 4.5 backspacing...". I think your refering to the bolt pattern there. But if I am thinking right, those have a 3&5/8" backspacing. I ran 15x10 with a 3.25 back spacing no problems and I can't think of any reason you would run into any issues either. Those are a popular jeep wheel and many people run them.
With a 15" wheel though you are limited though with your brakes. So if you have a big brake kit or are going to get one, you will want to research your options there cause it could be an issue.
With a 15" wheel though you are limited though with your brakes. So if you have a big brake kit or are going to get one, you will want to research your options there cause it could be an issue.