I highly recommend HOW TO REBUILD BIG-BLOCK FORD ENGINES by Steve Christ. Lots of info on casting numbers and interchangability. Heads will have a number something like C5AE 6090 F or C3AE 6090 J. Look between spark plugs for casting numbers and under valve covers for date code. The 427 blocks can be confusing. Some have 427 cast into them and some just have 352 and some nothing at all. I believe the date code is by the
oil filter adapter is I remember correctly. I would have to look again to be sure. Hope this helps, Jim