How close are you trying to get? The ball in the flywheel isn't true tdc, it takes into account the timing, which is what, 8 degrees before? Putting your thumb over the plug hole works, but you need to be turning the engine by hand, not with the starter. If you're trying to set the distributor, either method will get you close enough to start the engine. Otherwise, put a long pencil in the plug hole when the piston is near tdc.
