Something just hit me........you know one head is a 67 273 head; how do you know? The other is 68 to 74 yet you do not know the date cast, how do you know it is a 68 to 74? I ask this because to know one head is a 67 273 head, you would need to know date cast and it follows that you say the other head is 68 to 74, you would also need to know date cast, yet you just stated you are not sure how to narrow it down.
Something does not add up.
