Reading a little bit more into this it seems you might need a 1.25" wheel spacing in order for 13.5" to fit the 5.25" spacing. But would this be hard on the parts for the wheel to be further out and look weird as well?......To far out.
**Edit**
Found one of my answers...
Q: What are wheel spacers?
A: Wheel spacers are rings measuring 1.25"~1.5" thick, are typically made out of billet aluminum and are designed to be sandwiched in between your Jeep's axles and wheels. By installing wheel spacers, you will effectively reduce the amount of back spacing your wheels have allowing you to install wider than stock tires without having to replace your factory wheels.
Q: Are wheel spacers safe to use or do they cause extra stress on your axle or wheel bearings?
A: High quality wheelspacers, the kind that bolt up to your axle first are no more dangerous or cause any more stress to your axles then would a wheel with less backspacing. Anyone who tries to tell you otherwise doesn't know what they're talking about and I have yet to hear a single good or specific explanation as to exactly how they are worse. Just to be clear, the cheap-o spacers (the kind that you can get at PepBoys and are sandwiched between your wheel and axle using the existing wheel studs) are in fact EXTREMELY DANGEROUS. These cheap-o spacers leave little thread for your lug nuts to hold onto and can fail. DO NOT USE THESE!