I have a cast iron Bellhousing with the numbers 421 664 ! The Bellhousing to block pattern is correct for my Amc 360 with the exception of 2 missing bolt holes at the ten and two o'clock position ? Starter positioned on passenger side ! Shouldnt the correct bellhousing utilize 6 mounting holes ? btw thanks Bulltear for the V8 alternator bracket ! Worked perfect for the CS series alternator !