Silly Timing question

After manually timing the engine by simply twisiting the distributor, I decided to hook up a timing light and see exactly where the timeing was at. I hooked up the gun to the #1 cylinder. It appears as if the timing is WAY off when I hook the light up. I don't even see the timing mark on the harmonic balancer. The engine runs and idles fine, twisting the distributor in either direction causes the engine to start to idle rough... Is there anything that would cause this timing light to register this far off? The harmonic balancer only goes on one way. Could it be my chepo timing light?

If I can't get the engine timed with a light, I may try the vacume method suggested in another thread.