I am starting to collect parts for my 67 L30/M20. The block is numbers matching but I need heads, carb, and an intake. What date codes are "correct" if my Block dates to Mid - January, and the Cowl is the 4th week or March(03D)? Can you go a few weeks before, months before? I saw an intake for sale that matches but it is November of 66. Is there any rule in terms of a correct restoration - like car show rules or any guidelines? Thanks a bunch - I can't wait until spring...