Are there different flange lengths on Chevy engine cranks where the flex plate mounts?

Yes, there are different flange lengths on Chevy engine cranks where the flexplate mounts. The length varies depending on the engine family, generation, and even sometimes the specific application (e.g., truck vs. car). You can't assume all Chevy small-blocks or big-blocks have the same length. Always verify the length using a parts catalog or by measuring the crankshaft flange of the specific engine you're working on. Using the wrong flexplate can lead to significant problems, including misalignment and potential damage.