I measure from the ground to the underside lip of the fender right at the center of the front hub(I was doing this today). Make sure to drive it around a little before tightening the lock nuts, as it may settle some after your adjustment and you'll have to fine tune it.

And, yes, it takes a lot of turns to make a big difference.

John B.

'87 Raider 2.6 Turbo Auto, Under Construction
'95 Montero SR, 35x12.5/15 BFG M/T KM-2's, Rock sliders, Qtr panel chop, gas tank lift, 2" BL, Aisins, 5.29s
'95 Pajero Mini
'98 Montero Winter Ed.
'04 Cadillac XLR
'03 Kawasaki ZRX1200R
'60 Ford Falcon 4Dr