Would like to ask your opinion on a correct date for my 69 Cobra Jet intake manifold. The block casting date is 8/17/68, the engine assembly date is 8/27/68, the heads are dated 8/16 & 26/68 and the distributor is 9/10/68. The Marti Build Date is 9/19/68. The car is a early production car and I would appreciate some past experience when it comes to narrowing the date range. The manifold is probably an 'early ' C8OE-9425-C just need some advice on a date to help in the search. Thank You. Brian