I have a 1974 302 that I'm putting in my 66 wich had a c-4 and a 289, can I still use the old flexplate with that 302? Every thing I see is for 65-73,what about my 74
yes, in fact you have to use the early flexplate in this case as the mustang ll used a unique 148 tooth plate that wont work with your C4 bellhousing. and yes the balance factor is the same. it didnt change on the 302 untill 1981.