The "65" means the tire is 65% as tall as it is wide. Wider means taller. Going to a 70 series will make for taller tire at same width. Some sports cars (and some trucks) have big wheels and tires that look like black rubber bands around the wheel. This is a picture of a 354/25- 20 tire . It is 354mm or about 13" wide. It is 25% as tall as it is wide, 88.5mm or 3.4 inches tall. This is a HORRID setup for anything but racing on smooth pavement. Of roading it will beat your teeth out, and have ZERO flex for traction on rougher terrain. Pretty sure you can go with at least a 265 or even 275 /70 -17 tire to get plenty of lift which still fits fine in the wheel well.
It's measured at the diff. Tremor has taller tires and an altered suspension that gives it a factory lift if you will. Different control arms in front, different shocks and springs in rear. Between the tires and suspension, it's still under an inch for the increase - takes it to 9.7 clearance.
At the lowest point, usually the rear diff.
