correct adjustment on a panhard rod

I have had my pan hard rod for a couple of weeks and went to put it on when I realized I can't find the directions to adjust it. How do I adjust this thing to the correct measurement? I remember when I had the directions something about hanging a string off if it to get the correct measurement....plz help!!!

http://bmrfabrication.com/instructions/phr002.htm

Holy Crap that was fast!! Thanks for the quick reply...exactly what I was looking for!

-Travis

No problem. ;) Use a liberal amount of blue loctite - I have the older version with the adjusting nuts on both sides - I didn't use enough on the passenger side and when it came loose it rattled like crazy.