Rob,
As I use a hard point handle and do not have any adjustment for level, here is how I make my leadouts exactly the same length.
1. Install both leadouts to the bell crank.
2. Pull one leadout all the way out and make a very fine mark on both leadouts at the same point near the end of the leadouts.
3. Pull the other leadout all the way out and mark it across from the point where the first mark moved towards the wing tip.
4. You now have one leadout with two marks and one with only one.
5. Carefully measure the distance between the two marks on the one leadout and divide in half.
6. Measure and mark this half distance (between the two marks)on the leadout with the two marks.
7. Now bring the single mark on the other leadout to coincide with the middle mark on the other.
8. Clamp or tape the leadouts together.
9. Using small wire bending pliers (the type with the round rod on the end) make a full bend at the point you want the ferrule to be. (this works with cable or solid lead outs)
10. Do not worry about the leadouts catching on one another. If they are smoothly wrapped, they will never touch each other.
11. You now have two leadouts marked at exactly the same point (with a nice small radius bend) and your bell crank is parallel to the center line of the plane.
Kim.