'72 Longhorn questions, 1 of 3 postings

[oldasi]

I got this truck about 10 yrs. ago and haven't had a chance to do anything with it, retirement business kept be busy and now my patent rights expired I'm trying to get into cleaning it up and getting it presentable and road worthy.
Got the building history from GM Canada and finding it's not as was built, interior has been upgraded, looks like a long horn box was installed, engine and trans numbers are correct, match as built info but no serial number on frame at steering box.
This posting has 3 pictures of a shelve or bracket on the driver side just behind the cab, doesn’t look to be a bracket for holding a gas tank, see pics attached here