Mastersbilt serial number

[Franks4]

Does anyone know where they are located on car? Thanks

[TheJet-09]

On top of the LF frame rail between the left hand motor mount and where the interior starts (right behind where the LH header would be, in front of your feet). Not sure how old of a car you are talking about, but I know if the number starts with a zero, it is a Smackdown. Mine has an "M" after the number, which apparently means it is a MasterSbilt by Mars.