Original VIN# Problem

[jgoo72]

Alright so I have had my 72 chev for about a year now, I bought it for a project truck to slowly over the years build. When I bought the truck I knew it had a reassigned VIN# but didn't really think much of it. So here I am today, is there anyway I can recover the original VIN#. I looked on the chassis by the gear box and nothing, the one inside the door is the new state assigned VIN.

And while i'm here I believe my truck used to be a standard but the last guy who had my truck started to restore it and put a auto in. I looked for the linkage but don't exactly know what I'm looking for, any help would be awesome!