Hey bosscars, I answered his post before with information from an interchange I have(not ford) it lists the following for 68 Mustang 302 bellhousings:302-2V = C5AA-6394-A, cast aluminum, Mustang(including GT 350) 302 4V = C5AA-6394-B, cast iron.Same interchange also lists all 68 Mustangs with 302's recieved the 164 tooth flywheel.The 289's used two different bellhousings(according to this book) they were the old familar C5D6394-A before 2/15/68 and the C8ZA-6394-A after, both utilizing the 157 tooth flywheel.I have the C5AA-A aluminum bell on my own 66(took it off a 302 in a Fairlane at one time)with 164 tooth Ford flywheel and 11" clutch. I think that if you/he have the bellhousing and flywheel off, as mentioned by someone else above, the easiest thing to do would be see if the flywheel fits, a 164 tooth one won't fit to well with a small bellhousing.Would I would like to see cleared up is the various early 289 flywheels, I have seen numerous casting numbers and teeth count.Most people seem to say the 157 tooth is the correct count for the C5DA bell, but I have in front of me now, a January 1965 edition of the Ford Car Parts and Accessories Catalog, it lists the following flywheels and descriptions for the Mustang

art number C4OZ-6375-A for the 260 engines-160 tooth ring gear, for the 289 (non hipo) it lists the C3AZ-6375-F, but does not describe further, for the HIPO it lists the C3OZ-6375-C,used with C3OE-6380-B ring gear, but gives no description or listing of this part number.Under ring gears for flywheel in same Ford book it lists:for F special,and F,X 2/B and 4/b 289 a C2OZ-6384-A ring gear-described as 160 teeth, 13 1/4" O.D..I realize these are the box part numbers and not actual numbers to be found on parts.But it sure looks like they were talking 160 not 157 teeth in most instances, I have some of these Flywheels, but I have never sat down to count all those teeth, someone here did last week, and they found an original 289 flywheel they had assumed was 157 teeth, and it turned out to be 160 teeth ! I sure wish Bob Mannel had included flywheels and bellhousings in his book !
1967 S code GT Deluxe Coupe 65B
1966 Convertible 76B 289 4 speed
1964 Fairlane 500 2DR HT-the new project
1986 Jeep Cherokee 4X4 the "beater"
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