[rpred]

If possible always use "Build date codes" not casting numbers. On the 429/460's you can find it stamped on the machined surface at the upper right corner on the front of the engine block. The first digit is the calender year the next letter is the month A-M (I is not used A=January) the last two digits are the day of the month. (eg. 8B20C)= 1968 or 1978 February 20th.
Rick FF#3169 <460/tremec>