318 Flex plate question/ help

I advise against using a factory or factory replacement flex plate in any level of performance. I have had two that have had the ears sheer off. The last one had two that sheered off.
I recommend this flex plate BB MOPAR/DODGE/CHRYSLER 440 SFI CERTIFIED FLEXPLATE WITH THREE BOLT HOLES | eBay
It says it's for a big block but it'll work for small block too. It has both bolt hole sizes for 5/16" and 7/16".