I'm trying to identify the 235 in my 51 3100. I know it's not original.From the casting number I got that it is a 1958-1962 235. Also cast on the block is the code F29. Does that mean June 2 1959? Also the stamp on the distributor boss is F603B.I know F is Flint and I think 603 means June 3 (right?) but I can't find anything anywhere to identify the suffix code,the B. Anyone know what I have?Thanks---Jack
