I'm running 205 / 70 up front and 235/65 rear. On 8 inch 80s stock steel wheels. Scrub line is 3 inches. 1 inch with just wheels with no tire on it. This would simulate avflat tire and then some. Sid was great to work with. I initially thought I need drop Blocks on the rear as well. But he told me I didn't need them with the Posie springs. Unless i wanted a tail dragger. He was absolutely correct. I removed my front axle , drag link and steering arms and took them to Hershey and swapped him my core for the new stuff. Installed in less than a day.