Since Sportsman class can run full slicks now, I want to run them next year. I've decided to go with either a 9" or 10" by 26" Hoosier, 18120D06 or 18131D06. I would rather run a 26" than a 28" tire due to losing gear from the larger diameter tire. Only problem is I have to get new wheels for them. Hoosier does make a 16" slick but it is a 28" and I would rather run a 26". For $80/ea Diamond Racing Wheels has a 15x8 or for $87/ea has a 15x10. They will drill them in a 5x4.25 bolt pattern no problem. Now for the part I'm not sure about. The 15x8 can be made with a 5" backspacing and the 15x10 has a 6" backspacing. This appears to conform to the stock wheel but will they actually fit properly. I'm not sure about the offset but if the backspacing is good does the offset matter? Can someone help me out here? The wheels are made to order and cannot be returned so I want to be sure they'll fit correctly. Also, will the 10" slick clear the fender well Ok?