[bobcowan]

Aftermarket balancers often have multiple timing marks, because there are a variety of pointers available, both aftermarket and stock.

Remove all of the spark plugs. Put your thumb/finger over the #1 hole, and turn the engine over with a wrench/handle. You'll feel when that cylinder is on the compression stroke. When it stops pushing air, you're at the top of the compression stroke. Then you can look at your timing pointer, and tell which set of marks you're supposed to use.

If you have a hand made or adjustable pointer, you'll have to get fancy with a degree wheel and a piston stop.