V6 identification?? Strange

[Boots43]

I have a 63' special with a later model v6, 3.8L 231. TH350 trans. I am trying to figure out the year. Block casting # 25514290. I found an aluminum plate on the driver side front of the block with the #1226 big space 976393. No letters at all. Is the plate something a rebuilder may have put on? Next to that plate is stamped 000250. Any and all help is appreciated. I will try to attach a photo. Charlie

[bob k. mando]

should be a 79-84 engine.

http://www.buickgod.com/article/3242.html

i have no idea about the plate.

[Boots43]

Pulled off the alum. tag and no numbers behind it either. Pulled the alt. and bracket off again and no numbers there either. Tomorrow I will jack her up and climb under and search high and low. Getting to be a little frustrating. Wish me luck, Charlie