I am currently restoring a 69 SS 350 convt. camaro.The original engine and tranny were removed about 20 years ago.This is a x55 code.The vin is 124679n64704 time built is 05C.I want to put the correct time period block,heads,intake,and tranny back into this car.The block casting no. i am looking for is 3956618.The heads im looking for are 3927186.And the intake I need is 3927184.This will put togeather the correct L48 engine but I am not sure of the dates that would be correct for this car.Also does any one know if an M21 was an option for this car?I believe it came with an M20.One more question if im not pushing my luck already,what should the tranny be dated? Thanks for your help.