Thanks for all of the help on the location of build sheets, I pulled the gas tank and there it was, however it is completly unreadable, but it was there.thanks to all that helped, what would be the best thing to use to rub some of the dirt off without rubbing vital info away?

Before you try rubbing the paper with anything shine a mag lite or LED flashlight through the backside to see what you can read. It can be pretty brittle and you might just smear the dirt into it. Goodluck and congrats on finding yours!