i have loved ones up there! way cool! it's beautiful country in those parts. lived in Gridley and worked in Oroville myself for a while... anyways, wanted to welcome you (i see you're not that new anymore but, you know )
i think the Percy's wheel-rite tool might come in handy for you... allow you to run with "TECHGUY"'s info (yeah, oh gosh, it's not tech guy :doh: ) LOL! anyways... combined with his insights the Percy's tool may be what makes the difference. bend a template wire around the tires of your choice, set the gauge at your wheel's size and backspace and you swing the tool via the wheel hubs/axles and you'll witness any interference... swap the wires for a different size tire, change the tool's backspacing and you can pretty much determine exactly what will work and what won't.
might save you some headaches. many members unfortunately didn't check & confirm and bought non fitting, NON Returnable wheels... costs too much as it is buying wheels & tires once, let alone twice.