While waiting to put my geiser's on, I mounted up new 37" ko2's on stock wheels. No mods, no rubbing, bottom perch. Drives fine. Have been in and out of some deep gutters in forward and reverse to see if I could tear off my mud flaps. No luck. The reason being 37" ko2's tape out at just over 35" unmounted. That is a scab with 315 k02's behind my screw (obvioulsy also on bottom perch). Last pic is my unused old 315 spare side by side with a brand new k02 37". Roughly only an inch difference.