I adjusted mine by using a pointer I taped to the top of the steering wheel. I drove down a decent highway and marked on the dash where the pointer on the steering wheel lined up with each other.
Then I went back to my driveway and used the levelers to raise the front wheels off of the ground. With the wheels off of the ground I adjusted the Tru-Center so that the steering wheel pointer aligned with the mark that I put on the dash. That was all it took to have it adjusted so that I did not have to fight against it when driving down the highway. With the Tru-Center it took much less input from me to stay in my lane. .