Yes, you should lift the car off of the ground, loosen the adjuster bolts, lower the car to the ground and push it up and down several times to see the height. Lift the car when you adjust the bolts so that the bolt threads don't get damaged.
Yes, I agree. You might even need to drive it a little because the front tires tilt "in" when you jack the car off the ground and when you drop it back on the ground the tires get trapped in that tilted position. If you drive or at least roll it 10-12 back and forth the tires will again lay flat against the ground giving you a truer view of the front end height.
Good Luck....
