right stuff rear disc adjustment

[usa-69z]

Guys , i am having major dramas setting up my rear disc or emergency brake adjustment on my right stuff rear calipers..what the problem is that the arm that you must adjust before bleeding has a hex spline that you move the arm around on to get the right position. So when i turn the spline into the correct position for the e brake the arm will not go on as it is limited by the stopper at each end of the movement. I hope this makes sense..
has anyone had any experience with this???

thanx, Gav