I did the same as Metal Storm,but I cheated a weee bit by using another rocker shaft and cutting it down so you are only dealing with two rockers on a very short shaft.

Next question: What is the formula for determining the difference between a 1.5 and a 1.6 rocker arm NOT at full lobe lift? Lets say I want to calculate the difference in lift at 15 degrees ATDC? Do I measure ACTUAL lobe lift(on the lifter) at 15 degrees ATDC then X 1.6 and compare it to what I have actually measured with a 1.5 rocker arm at the retainer?????