11-30-2013, 08:42 AM
Here's a link I found that may be helpful for you. It contains some good detailed information as well as comparisons between the 351 4-V and CJ's motors for the 71 and 72 years. Based on your information it appears the correct flywheel would be the 28.2oz.
http://www.boss351registry.com/351_Cleveland.htm
http://www.boss351registry.com/351_Cleveland.htm