Ray, you might want to clean up the area where you are reading the numbers. I have two numbers that are very close and easy to mistake if not clearly read right. Double check, I think that your number "3927768" should be -3927763- and your number "3982084" should be -3962084-. If the numbers I provided are correct, then both are from '62-'79 250 block. Let us know what you find.
