The mesurement should be done some wehere on the frame , in front of the T bar
Bolts that hold bottom A arm is a perfect spot
dont put chalk on the adjuster bolt, it will be take off by the socket, and you will be left with no means of counting turns
take a sharp nail, and scratch one side of the adjuster bolt, and then you will know exsactly how many turns you did
you can get about 2 inches of lift, but thats pushing it to the max, and the ride will suffer
1-2 inches is what people are geting from T bar lift
goto
www.maxc.org, and check out the instructions