I am at a loss!! I have a '65 Mustang with a '72 302 stroked to a 347. The transmission is a C4 with a Converter designed on the 11.4 bolt pattern. This requires the 164 tooth (So I'm told) flex plate. I understand that the original flex plate was 157. When we were putting all this together, the bellhousing and the engine plate did not mate correctly in the starter location. I am trying to find out if the bellhousing was made slightly larger for the 164 tooth flexplate? If so, can someone tell me which model Mustang came standard with the 164 tooth flexplate? Once I know which car originally had this installed, I can then order a replacement engine plate. It seems no-one (not even FORD), can answer this question!!