Those unfortunately aren't going to answer your question. On the passenger side, up in front of the head is a pad which is stamped with some letters and numbers. (V0508CWA for example) The last three will get you what you want to know. If, and it is a sketchy if, the original intake is still on it, the casting numbers (and date code) will help you in your quest. If (yeah I know, another if) you can get a valve cover off of it, the head casting number/date code may also assist.